Sulfination of Aryllithium Compounds Preparation of Sodium o-, m-, and p-n-Dodecylbenzenesulfonates

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PURDUE UNIVERSITY

THIS IS TO CERTIFY THAT THE THESIS PREPARED UNDER MY SUPERVISION

BY________ Joseph F« ly o n s

e n title d

S u lf in a t io n o f A r y llith iiim Compounds.____________

P re p a r a tio n o f Sodium o - ,

, and g-n-~D odecylbenzenes u i f o n a te s

COMPLIES WITH THE UNIVERSITY REGULATIONS ON GRADUATION THESES

AND IS APPROVED BY ME AS FULFILLING THIS PART OF THE REQUIREMENTS

FOR THE DEGREE OF

D octor o f P h ilo so p h y

P r o f e s s o r i n C h a r g e o r T h e s is

H ea d o r S c h o o l o r D e pa r t m e n t

TO THE LIBRARIAN:-----

-16THIS THESIS IS NOT TO BE REGARDED AS CONFIDENTIAL

p s o i 'e b b o b

G HAD. SC H O O L FO RM B—3 - 4 9 — 1M

n r

ohabgh

SULFINATION OF ARXLLITHIUM COl'IPOUNDS. FREPÀRATIOM OF SODIUM o-,

m-,

ÂHD ^-n-DœEC^ME^EIŒSULFONATES

A Thesis Submitted to the Faculty of

Purdue University by

Joseph F# lyons In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy June, 1950

ProQuest N um ber: 27714098

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uest ProQuest 27714098 Published by ProQuest LLC (2019). C opyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States C o d e M icroform Edition © ProQuest LLC. ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106 - 1346

ACKNOEEEDGMENT

The author is greatly indebted to Dr* William. E* Truce and to Dr. E* T. Mcbee who have been in direct charge of this research*

Thanks are also extended to Dr. Harry Galbraith who

performed the analytical work* This research was conducted as a Purdue Research Foundation Fellowship sponsored in turn by the Procter and Gamble Company to whom the author expresses his sincere gratitude*

TABLE OF COHTENTS Page ABSTRACT

i

BîTRGDUCTIOlî..............................................................................................................

1

PART I - THE PREPARATION OF BARIUMo-, m-, AND g-TOLUENESUIFONATES

3

I n tr o d u c tio n .

................................

Experimental

3 * . . . . . .

. ..

3

PART II - TUB PREPARATION OF SODIUMo-, m-, AND g-n-DQDECriBENZENESULFONATES . . . . 7 ....................................................11 Introduction . . . . . . . . . . . . . . . . . . . . . . . .

11

Experimental . . . .

12

..................................................

. . . . . . .

PART III - THE PREPARATION OF SODIUMg-IAUROYLBENZENESULFONATE. REDUCTION TO SODIUM^-n-DODECYIBENZENESUIFONATE . . . . . . Introduction • • . . .

...................................... . . . . . . . . . .

Experimental......................

................................

Experimental . . SU M M A RY

..................................................

................................................................

BIBLIOGRAPHY.................................................. VITA

2h 2h

PART IV - ALKYLATION EXPERIMENTS W ITH n-DODECYL £-TOLUENESUIFONATE............................... 7 . . . . Introduction

2h

................................................................................................. .

28 28 28 31 33

LIST OF TABLES Table 1.

Page Preparation of Sodium £-Laurcylbenzenesulfonate . . . .

25

( Contribution from the Department of Chemistry, Purdue University)

SULFINATION OF ABYLUTHCUM COM POUNDS. THE PREPARATION OF SODIUMo-, m-, ANDg-n-DODECYISENZENESUIFONATES1

(1)

Based on a thesis submitted by Joseph F. lyons in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Purdue University, June 1950. By William E. Truce, E* T. McBee, and Joseph F* lyons^

(2)

Present address :

The Texas Company, Beacon, New York.

ANABSTRACT During the course of preparing some high molecular weight sodium alkylbenzenesulfonates, the conversion of aryl halides to salts of the corresponding arylsulfonic acids was investigated. Sulfinic acids have been prepared by the reaction of Grignard reagents with sulfur dioxide^»^; these are readily oxidized to (3)

Rosenheim and Singer, Ber., 37, 2352 (190U)*

(10 Marvel and Johnson, J. Org. Chem. , 13. 822 (I9I48). sulfonic acids^*^.

In view of the versatility and greater reactivity

(5)

Haim, This Journal, 5%, 2166 (1935).

(6 )

Doering and Beringer,Jbid., 71, 2221 (19U9).

of organolithi-um compounds5 the preparation of salts of s uLfonic acids via the corresponding organolithium intermediates was studied* p-Tolyllithium was sulfinated at 0° with dry sulfur dioxide* The reaction mixture was hydrolyzed and p-toluenesulfinic acid was isolated in 68%yield based on g-bromotoluene.

I t was subsequently

converted to the corresponding barium sulfonate using hydrogen peroxide, in an overall yield of 60%based on the aryl bromide. Similarly, m-bromotoluene and o-bromotoluene were converted to the corresponding sulfonates. To compare this procedure with that employing the Grignard reagent, g-tolylmagneslum bromide was likewise sulfinated*

Although

the sulfination appeared to proceed satisfactorily, hydrolysis of the reaction mixture required prolonged treatment with dilute acid* The yield of ip-toluenesulfinic acid was low (20%) and a substantial quantity of a neutral material, ra.p* 92-3°, was isolated.

This is

the recorded melting point of di-g-tolylsulfoxide^ which may have

(7)

Parker, Ber*, 23, l 8Wi (1890),

been formed through the course suggested by Burton and Davy®.

(8 )

Burton and Davy, J. Chem* Soc., 528 (19U8). g-Chiorotoluene was also converted to the barium sa lt of

g-toluenesulfonic acid via g-tolylüthium, thus accomplishing a conversion which is not possible through the Grignard reagent.

Jn order to test this method on higher homologs3 g-bromolaurophenone (II) Tiras prepared from ^-bromobenzqyl chloride and di-n-hendecy1cadjEdLnni^•

(9)

This ketone was reduced to p-bromo-n-

Cason, This Journal, 6 8 * 2078 (19^6).

dodecylbenzene (I) using a variation of the Wolff-Kishner method^.

(10) Huang-Einlon, ibid., 6 8 , 2U87 (19U6). Although this aryl bromide reacted sluggishly or not at all with magnesium, i t reacted readily with lithium and the resulting product was readily sulfinated*

Following the same technique used on

the lower homologs, with the exception that sodium permanganate was used as the oxidizing agent, sodium p-n-dodecylbenzenesulfonate (IV) was prepared in bB% yield based on the aryl bromide. m-Bromo-n-dodeeylbenzene and o-bromo-n-dodecylbenzene were prepared analogously and converted to the corresponding sodium sulfonates. As an alternate method of synthesizing sodium p-n-dodecylbenzenesulfonate, g-bromolaurophenone was treated with aqueous sodium sulfite at elevated temperature and pressure to give sodium £~lauroylbenzensulfonate in 29% yield.

The latte r compound was

then reduced by the Clemmensen method to give sodium p-n-dodecylbenzenesulfonate in fair yield.

EXPERIM ENTAL A* Synthesis of Isomeric Barium ToluenesTJLHona.'bes. Barium £-Toluenesulionate.

£-Tolyllitiiium was prepared

in the usual manner^rom 3h»2 g. (0 .2 0 mole) of g— bromotoluene

(11)

Gilman, Zoellner and Selby, ibid.,

55,

and 3mh g. (0*1% .8 g. atom) of lithium metal.

1252 (1933). A total of ZL50 ml. of

ether was present after the addition of the aryl "bromide.

Conver­

sion to ;p-tolyllithium was found by the standard titratio n method to be practically quantitative.

The solution was then cooled in

an ice bath and dry sulfur dioxide was passed through the stirred mixture for one hour,

hydrolysis was effected by pouring the mix­

ture into ice and dilute aqueous base.

The alkaline layer was

separated, just acidified with hydrochloric acid, and ether extracted. Evaporation of the ether gave g-toluenesulfinic acid in 63% yield. This acid was treated with a slight excess of barium hydroxide solution and the mixture was stirred vigorously while an excess of 1$% hydrogen peroxide solution was added in small increments.

After

boiling the solution to remove the unused peroxide, carbon dioxide was introduced to precipitate the excess barium ion as the carbonate. The insoluble material was filtered and the filtra te evaporated and dried at 60° to give mono-hydrated barium g^-toluenesulfonate {33% based on the sulfinic acid). bromide was 60^.

The overall yield from the aryl

An S— benzylthiuronium. derivative, m.p. 182°, was prepared; reported1^, m.p. 182°•

(12)

I t did not depress the melting point of an

Chambers and Watt, J. Org. Chem., 6, 376 (I9I4I ) .

authentic sample of S-benzylthiuronium g-toluenesulfonate. Barium m-Toluenesulfonate. — Following the same sequence of steps, the mono-hydrated barium salt of m-toluenesulfonic acid was prepared from m-bromotoluene in 33%yield.

An S-benzyI t Muronium

derivative, m.p. 155- 6°, was prepared. Anal. Calcd. for

^

S.28.

Foundt

N, 8.30.

No melting point depression was observed with a mixture of this derivative and one prepared from an authentic sample of m-ioluenesulfonic acid obtained by oxidation of m-thiocresol. Barium o— Toluenesulfonate*

— In a similar fashion, barium

o-toluenesulfonate was prepared from o-bromotoluene in 31%yield. The low yields for the ortho and meta isomers were believed to be due in part to the instability of the intermediate sulfinic acids^*^*

(13)

Troeger and Yoigtlander-Tetzner, J. prakt. Chem. $ Sh9 513 (I8 9 6 )

(1U)

Troger and EULe, ibid., 71, 201 (1905).

As a precaution (to reduce the decomposition of the intermediate o-toluenesulfinic acid) all solutions used for hydrolysis and extraction were kept at 0° and the add was kept out of contact with air as much as possible.

v±

An S-benzyCLbhliironium derivative, m.p. 179«5-lS0.5o (after drying at 77° in vacuo), was prepared. Anal. GaXcd. for

Founds

U, 8.33.

No melting point depression was observed with a mixture of this derivative and one prepared from an authentic sample of o-toluenesulfonic acid obtained by oxidation of o-thiocresol. B.

Synthesis of Isomeric Sodium n-Dodecyibenzenesulfonates. Starting Materials. - (a)

(15)

n-Hendecyl bromide*^ was purified

Columbia Organic Chemicals Co., Inc., Columbia, S*C.

by washing successively with cold concentrated sulfuric acid, sodium carbonate solution, and finally with water until the extracts were neutral.

After drying, the product was fractionated through a

Vigreux column (IS1 *).

The fraction boiling at 102° (U mm.) was

collected. (b)

p-Bromobenzoyl chloride, b.p. 127° (16-17 mm.), was

prepared in 92% yield from g-bromobenzoic acid and thionyl chloride. (c)

m-Bromobenzoyl chloride, b.p. 122— 3° (17 mm.), was

prepared in 93% yield from m-bromobenzoic acid and thionyl chloride. (d)

oj-Bromobenzoyl Chloride, b.p. 120-1° (15-16 mm.), was

prepared in 95% yield from £-bromobenzoic acid and thionyl chloride* (e)

Thionyl chloride was specially purified by the method of

Fieser*^.

(16)

L. F. Fieser, **Experiments in Organic Chemistry1 *, D. C. Heath and Co., NewYork, N. Y., ±9bX9 p. 381.

(f )

Sodium permanganate solution was prepared by adding a slight

excess of sodium sulfate to a solution of barium permanganate and filtering. g-Bromolaurophenone (IX). — This compound was prepared in 22-51$ yield by the general procedure described by Cason^. n-Hendecylmagneslum bromide was prepared from 117 g* (0.50 mole) of n-hendecyl bromide and 12*2 g. (0.50 mole) of magnesium in 300 ml. of ether.

The entire reaction was carried out in an

atmosphere of dry oxygen-free nitrogen.

The reaction mixture was

cooled to 0° and 50.U g. (0.27 mole) of anhydrous cadmium chloride added over a five minute interval.

After the addition of 100 ml.

more ether, the reaction mixture was refluxed until a negative Color Test 1^*7 was obtained (three hours).

(17)

Gilman and Schulze, This Journal. U7, 2002 (1925). The ether was then removed and replaced with 300 ml. of

benzene in the conventional manner.

To the stirred reaction mixture

was added 8 7 .8 g. (O.UO mole) of g-bromobenzoyl chloride in 100 ml. of benzene over a one-half hour period. applied to maintain reflux.

Gentle heating was

After the final addition the mixture

was stirred and refluxed for three hours and then hydrolyzed by pouring into 10% sulfuric acid solution and ice.

The benzene

layer was separated and washed successively with 5 %sodium hydroxide solution and water.

The solvent was removed and the residue

v iii

recrystallized from petroleum ether (30-60°) to give 73 g» (5h% based on the acid chloride) of product, m.p, 59-61°• Further recrystallization brought the melting point up to 62— 3°. Anal. Calcd. for CiQHgyOBr: Found:

C, 63.55

H, 7.90;

C, 63.763

H, 7.96;

Br, 23.57•

Br, 2U.2.

A 2,U-dinitrophenylbydrazone, m.p. III4.-50, was prepared. Anal. Calcd. for c2l4.^31%0l|.Brî

^°«79.

Found:

N, 10.80.

p-Bromo-n-dodecylbenzene (l). — p-Bromolaurophenone was reduced by the Huang-ÎÆLnlon variation^) of the Wolff-Kishner reduction.

However two modifications were introduced:

(1)

a large

excess of hydrazine was employed and vigorous stirring was main­ tained throughout the reduction because of the relative insolubility of this phenone in di ethylene glycol*

(2 )

less debromxnation and

better yields were observed i f the recommended time allowed for hydrazone formation was prolonged before raising the temperature to produce the desired hydrocarbon. To 52.7 g. (0.16 mole) of £-bromolaurophenone in a 1— 1. flask equipped with a thermometer and stirrer were added 210 ml. of di­ ethylene glycol, 21 g* of sodium hydroxide, and 50 g. of 85% h y d r a z in e

hydrate.

This mixture was stirred and heated at approxi­

mately 100° for twenty-four hours.

A small aliquot was withdrawn

and a negative te st for ionic bromide was obtained.

Excess hydrazine

and water were then removed until the temperature reached l 8U°. mixture was stirred at this temperature for eight hours. cooling i t was poured into water and ether extracted.

The

After

Bromide ion

équivalent to 8%of the orignal g— bromolaurophenone was found in the aqueous layer. After removal of the ether, the organic residue was distilled from a Claisen flask to give 30.2 g. (60%) of g-bromo-n-dodecylbenzene, b.p. 190-1 ° (U mm.), r^°

1.503k.

Anal. Calcd. for C-^gHgpBr: Found:

Br, 2^.7;

C, 66.70;

Br, 2U*58$

C, 66.50;

H, 8.92.

H, 8.89.

g-n-Dodecylbenzenesulfinic acid ( I I I ) . — To a 500-ml. three-neck flask equipped with a reflux condenser, stirrer, and a means of maintaining a positive pressure of pure nitrogen, was added 1.5 g. (0.22 g. atom) of finely divided lithium.

The la tte r

had been pounded out into thin strips and then cut with scissors to fa ll directly into the flask.

Over a one-half hour period,

2 9 .2 g. (0 .0 9 mole) of g-bromo-n-dodecylbenzene in 120 ml. of dry ether was added to the lithium, after which the mixture was stirred and refluxed for one hour.

In a separate experiment the yield of

the aryllithium intermediate was found to be 73%by direct titratio n . The flask was then immersed in an ice bath and dry sulfur dioxide was passed through the stirred solution for one hour.

An

additional 100 ml. of dry ether was added during the sulfination. Preliminary experimentation indicated that hydrolysis and extraction resulted in emulsions very difficult to break.

Consequently, the

reaction mixture was centrifuged and the ether layer decanted from the residue.

The latte r was washed twice with ether by centrifu­

gation and subsequently dislodged from the centrifuge bottle with

X

dilute acid* ether#

This formed a suspension which was extracted with

The la tte r was dried with Drierite, filtered, and evaporated

to give a 63%yield of crude g-n-dodeeylbenzenestilflnic add (sup# U9-5>1°) •

The product, recrystallized twice from petroleum ether,

was a white powder, m#p» 5 U-5 0, which slowly turned yellow on standing# Anal# Calcd. for C^gHg^SOgH: Found;

C, 70*0;

C, 6 9 *6 8 ;

H, 9 *6 7 *

H, 9*6!$#

Sodium £-n-Dodecylbenzenesu3fonate (IV)# — To 17*0 g# (0 .0 5 5 mole) of |w*-dodecylbenzenesulfinic acid was added 200 ml# of 2%sodium hydroxide solution and a slight excess of a h% sodium permanganate solution (peroxide oxidation caused excessive foaming). The temperature was maintained between 35-UO° during the oxidation. After standing overnight excess permanganate was reduced with sodium sulfite and the mixture was heated to boiling and filtered hot.

The

filtra te was neutralized with sulfuric acid and evaporated to dryness# Hot ethanol extraction of the dry salts gave 13*1$ g* (10%) of sodium g-n-dodecylbenzenesulfonate. Anal. Calcd* for C^g^^SO^Na:

Ha, 6#60.

Found:

Ha, 6.56#

The product yielded an S-benzylthiuronium salt, m.p# 95-7°* However, after drying at 77° (2 mm.) for forty-eight hours prior to analysis, the melting point was found to be 117- 8° after softening at 1 0 0 °# Anal# Calcd. for C26%0^2^3^2"

N, 5.69.

Found;

H, 5*68#

The product also yielded a g-toluidine salt, m.p. 138-139*5°, after drying at 77° (2 ram.)*

Anal# Calcd# for C25H39SO3ÎIÎ

H, 3*23*

Founds

N, 3*26#

m-Broinolaurophenone• — This compound was prepared from m-bromobenzoyl chloride and di-n-hendecylcadmium as described for (II)* The crude ketone was obtained by distillation from a Claisen flask in a nitrogen atmosphere#

Those fractions (b#p# 170-200°,

1—2 mm*) which gave a positive ketone test were combined for further purification*

The product was separated from a persistent

contaminant, n-docosane, by dissolution in glacial acetic add and filtratio n of the insoluble hydrocarbon# with water and ether extracted#

The filtra te was diluted

After washing the ether extracts#

successively with 2% sodium hydroxide solution and water, the ether layer was dried and evaporated#

The product was further

purified by fractional r©crystallization from 2 : 1 methanol-acetone to give a 20% yield of product, m#p* 25-30°#

The sample submitted

for analysis melted at 29- 30°• Anal# Calcd# for C^g^^OBr: Bound:

C, 6 3 .3 5

C, 6 3 .7 6 5

H, 7*96#

H, 7*89.

The ketone yielded an orange 2,U-dinitrophenyllhydrazone, m.p# 103-1$°, after drying at 77° (2 mm*)# Anal* Calcd# for C2l^h3^^O^Br:

N, 10.79*

Found:

H, 10*89*

m-Bromo-n-dodecylbenzene. — To a mixture of 33*1$ g* (0*10 mole) of m-bromolaurophenone, 12$ g. of sodium hydroxide, and 135 ml* of diethylene glycol, was added 32 g* of 85%hydrazine hydrate* The reduction was carried out as described for (I).

Bromide ion

equivalent to 3%of the bromophenone was found in the aqueous

layer#

A 60%yield of crude m — bromo— n— dodecylbenzene, b *p.

182-1 9 2° (3 mm#) was obtained by fractionation through a 15“ Vigreux column*

Over 80% of this product boiled between 188— 192°

(3 mm*), n § ° 1*501$!$* Anal* Calcd. for C^gHg^Br; Founds

C, 66*85

H, 9*05|

C, 66*505

H, 8*925

Br, 2l$*58*

Br, 2l$*52*

m-n-Dodecylbenzenesulfinic acid# — This compound was prepared in !$!$%yield from 15.0 g# (0 #0!$6 mole) of m-bromo-ndodecylbenzene and 0*77 g* (0*11 g. atom) of lithium in the manner described for (III).

The yield of the aryllithium intermediate was

78% * The sulfinic acid after two recrystallizations from petroleum ether was a white powder, m.p# 63- 1$°, which became yellow on standing# Anal* Calcd* for O^gHg^SOgH: Found:

C, 6 9 . 8O5

G, 6 9 .6 8 5

H, 9*67*

H, 9*68*

Sodium m-n-Dodecylbenzenesulfonate * — This compound was prepared in 80%yield from 5*7 g* (0,018 mole) of m-n-dodecylbenzenesulfinic acid as described for (IV)* Anal* Calcd* for CigHgpSO^Ha:

Na, 6*60*

Found:

Ha, 6*62*

The product yielded an S-benzylthiuronium sa lt, m*p* 97-8°, after drying at 77° (2 mm#)* Anal* Calcd. for

5

5*69#

Found:

H, 5*66#

A £-toluidine salt was likewise prepared, m.p. 103-!$°, after drying at 77° (2 ram.)* A nal* C a lcd . f o r C25H39SO3N:

N, 3*23#

Found:

H, 3*31 »

xü i

o-Bromolaurophenone• — — This compound was prepared from o— bromobenzoyl chloride and di— n— hendecyIcadmium. as described for (II)*

The crude ketone was dissolved in 2:1 methanol:acetone,

cooled, and filtered to remove a small amount of n-docosane*

The

filtra te was evaporated and the residue fractionated through a 15" Vigreux column under nitrogen to give a 33% yield of product, b.p. 187-189.5° (1-2 mm.}, ng°

1.5116.

Anal. Calcd. for C^gHjjyGBrJ Founds

C, 63.90;

H, 7.98;

C, 6 3 .76;

H, 7 . 96;

Br, 23.57

Br, 23.32.

To obtain a good yield of the 2,L-dinitropheoylbydrazcne i t was necessary to reflux a mixture of the bromophenone and 2, 1$ —dinitrophenylfcydrazine in an acid-ethanol solution overnight* Cooling deposited yellow crystals which were dissolved in pentane and filtered to remove unreacted reagent* gave yellow crystals, m.p* 68-9°.

Cooling the filtra te

The product was purified

chromatographically to remove an otherwise persistent impurity and dried at i$0° (1 -2 mm.) m.p. 70-1°. Anal* Calcd* for c2l$H31®U°UBr5 ^

10*79.

Found:

N, 10*81.

o-Bromo-n-dodecylbenzene. — To a mixture of 53*2$ g* (0*16 mole) of o-bromolaurophenone, 21 g* of sodium hydroxide, and 205 ml* of diethylene glycol was added 5>0 g* of 85% hydrazine hydrate*

The reduction was carried out as described for (I)*

Bromide ion equivalent to 15% of the bromophenone was found in the aqueous layer*

The crude product was fractionated

through a 151 1

Vigreux column under nitrogen to give 26*5 g* (52%) of o-bromo— r>dodecylbenzene, b.p. 17U-6 ° (2 mm.), Anal. Calcd* for C^gHg^Br: Found:

G, 66.65;

H, 8.72;

1.5060.

C, 66.50;

H, 8.92;

Br, 2l$.58.

Br, 2U.3*

Sodium o-n-Dodecylbenzenesulfonate. — To 1.0 g. (.11$ g* atom) of finely divided lithium was added 17 g* (0 .0 5 2 mole) of o-bromo-n-dodecylbenzene in 80 ml. of dry ether.

In a separate

experiment the yield of the aryllithium intermediate was found to be 90%.

Sulfination in the usual manner failed to precipitate the

desired lithium sulfinate.

However when a small sample was with­

drawn from the reaction mixture and the solvent and sulfur dioxide removed under nitrogen, the residue was found to be neutral on hydrolysis.

With another sample treated similarly a negative Color

Test 1^-7 was observed.

The diethyl ether was evaporated from the

reaction mixture and replaced by petroleum ether, 30-60°. Awhite solid which proved to be lithium bromide settled out immediately and was filtered*

The filtra te slowly became turbid

on standing at room temperature and a brown gelatinous solid collected after two hours.

This crude lithium sulfinate, separated and

washed by centrifugation, weighed 6 .7 g. (1* 1 %) after drying. Four grams of this product was oxidized with sodium per­ manganate as described for (IV) to give 1.7 g. (38% based on . the lithium sulfinate) of crude sodium o-n-dodecylbenzenesulfonate. The product yielded an S-benzylthiuronium sa lt, m.p* 100-1°, after drying at 77° (2 ram.).

XV

Anal> Calcd, for C26H U0®203^28

5#69#

Found:

5#69*

When mixed with the related derivative of the meta isomer (m,p, 97— 8°) the mixture melted at 85-7°• Sodium. £-Lauroylbenzenesxilfonate, — Amixture of 20*0 g* (0*059 mole) of £-bromolaurophenone, 50 g* of sodium sulfite, 2 g* of cupric sulfate and 500 ml, of water was shaken in a 1-1, iron autoclave for four days at 180° followed by two dgrs at 220°, After cooling, the contents were emptied and filtered*

The

insoluble material was extracted with ether to recover 7*0 g, (0*021 mole) of unreacted p-bromolaurophenone,

The residue after

ether extraction was re crystallized from hot ethanol to give 6,1 g. of sodium g-lauroylbenzenesulfonate.

This is a 29% conversion

based on the amount of phenone charged* Anal, Calcd, for C28 H27OSOjNa:

Na, 6*35*

Found:

Na, 6.27*

The product yielded an S-hen^ylthiuronium derivative, m*p, 166-7°* after drying at 77° (2 mm,). Anal. Calcd. for 8^N^8°^8^N^:

N, 5.53-

Found:

N, 5*5U*

Reduction of Sodium ]>-Lauroylbenzenesulfonate by the Clemmensen Method. Five grams (O.OlU mole) of sodium g-lauroyl' % benzenesulfonate was reduced with 20 g* of amalgamated zinc, 25 ml. of concentrated hydrochloric acid, 5 ml. of glacial acetic acid, and 20 ml. of water.

After r©fluxing for twenty hours the mixture

was decanted from the zinc and evaporated to jet*

dryness under an air

The residue was dissolved in hot ethanol and then cooled to

give the crude zinc sulfonate relatively free of zinc chloride.

The

crude product was digested with dilute sodium carbonate solution and

filtered. dryness.

After neutralization, the filtra te was evaporated to Hot ethanol extraction of the residue gave two grams

of crude sodium g-n-dodecylbenzenesulfonate from which an S-benzylthiuronium derivative was made. zations and drying i t melted a t 113°.

After repeated recrystalli­

When mixed with an authentic

sample of S-ben2yI t hiuronium g-n-dodecylbenzen©sulfonate (m.p. 117-8°) prepared from 17 the melting point was III4.-80.

Acknowledgment. — This work was supported by a grant frcm The Procter and Gamble Company to whomwe are greatly indebted.

SU M M A RY 1.

The conversion of an aryl bromide or chloride to the

salt of the corresponding sulfonic acid has been accomplished ty preparing the aryllithium compound, sulfinating i t , and then oxidizing the sulfinic add to the desired product.

This method is

to be preferred in some cases over the use of the Grignard inter­ mediate in this type of synthesis* 2.

The following new compounds and/or their derivatives

are described:

0- ,

and g-bromolaurophenones; o-, m-, and

p— bromo-n-dodeeylbenzenes5 o-, m-, and £-n-dodecylbenzenesulf ini c adds; o-, m-, and ^-n-dodecylbenzenesulfonic acids; and sodium g-laxiroylbenzenesulfonate.

SULFINATION OF ARYLLITHIUM COM POUNDS. THE PREPARATION OF SODIUMo-, m-, AND p-nDCDECYLBENZENESULFONATES INTRODUCTION The purpose of the present work was to prepare by an unambiguous method sodium o-, m-, and g^n-dodecylbenzenesulfonates. Direct sulfonation of an alkylbenzene with the usual sulf onating agents generally gives a mixture of isomers from which i t is difficult to isolate a pure product.

Recourse had to be taken to the so-called

"indirect" methods of introducing the -SO3N & group.

The path

followed in the present research was to investigate methods for the preparation of n-alkylbenzenesulfinic acids of known orientation. These intermediates were then oxidized to the desired products. One of the common ways of preparing sulfinates is to react an organomet a lii c compound with sulfur dioxide (22) (35).

This

method was used in the present work because the compounds necessary for this type of synthesis, o-,

and £-bromo-n-dodecylbenzenes,

could be prepared by accepted methods.

Furthermore sulfination of

an organometallic compound should give a product of known orienta­ tion.

Heretofore, the organometallic compound sulfinated was the

Grignard reagent.

In view of the versatility and increased reactivity

of organolithium compounds, a study of their reaction with sulfur dioxide appeared worthy of investigation. on this reaction in the literature.

No work has been reported

The use of aryllithium compounds would offer several advan­ tages besides giving an intermediate of increased reactivity.

An

aryl chloride could be converted to the corresponding sulfonate. This conversion is impossible or very difficult via the Grignard intermediate.

By the use of metalation and interchange reactions

with n-butyllithium, difficultly obtainable sulfinates could be prepared.

3

PART I THE PREPARATION OF BARIUMo-, m- 3 AND ^-TOLUENESULFONATES Introduction Before carrying out the somevÆiat tedious preparation of o~, m - 9 and ^-bromo-n-dodecylbenzenes5 I t was decided to te st the feasibility of the reaction of aryl l i thium compounds and sulfur dioxide with more readily available halides. reason the isomeric (o-,

For this

and £-) bromotoluenes were used in

the development w>rk described here. Experimental Conversion of g-Bromotoluene to Barium p-Toluenesulfonate via £-Tolyllithium* lithium. (3 ,2j. g,5 0 ,U8 g, atom), wetted with xylene, was pounded into a thin sheet and then cut with scissors directly into a three-neck flask in an emerging stream of dry oxygen-free nitrogen.

The flask contained approximately 70 ml. of

ether and was equipped with a mercury-seal stirre r and a means of maintaining a positive pressure of dry oxygen-free nitrogen, g-Bromotoluene (3 k * 2 g*, 0,20 mole) in 80 ml, of ether was added to the flask over the course of one hour during which time stirring was maintained,

Reflmting was spontaneous.

After the fin al

addition, heat was applied and stirring continued for an additional one-half hour. The reaction mixture was allowed to cool to room temperature and then forced under nitrogen pressure through a glass wool filte r

u

to a special flask for taking aliquots.

The conversion to £-

tolylHthium was found by the standard titratio n method to be practically quantitative •

The solution was then cooled in an ice

bath and dry sulfur dioxide was passed through the stirred for one hour,

mixture

hydrolysis was effected by pouring the mixture into

ice and dilute aqueous base.

The alkaline layer was separated, just

acidified with hydrochloric acid, and ether extracted.

Evaporation

of the ether gave p-toluenesulfinic acid in 68 % yield. The la tte r was treated with a slight excess of barium hydroxide solution and the mixture was stirred vigorously while an excess of 15># hydrogen peroxide solution was added in small increments (10).

After boiling the solution to remove the unused

peroxide, carbon dioxide was introduced to precipitate the excess barium ion as the carbonate.

The insoluble material was filtered

and the filtra te evaporated and dried at 60° to give mono-hydrated barium g-toluenesulfonate (88%based on the sulfinic acid).

The

overall yield from the aryl bromide was 60%. Anal. Calcd. for (C7H7SO3 ^Ba*H2O: Ba, 27.60; HgO, 3.62. Founds

Ba, 27.35

HgO, 3.U.

An S-benzylthiuronium derivative, m.p. 182°, was prepared; reported, m.p. 182° (3).

When i t was mixed with a derivative prepared

from an authentic sample of ]>-toluenesulf onic acid, no melting point depression was noted. Conversion of g-Bromotoluene to Barium ]>-Toluenesulfonate via p-Tolylmagnesium Bromide.

£- Tolylmagnesium bromide was prepared

5

in 92$ yield in the usual manner from lu9 g* (0*20 mole) of magnesium and 3lu2 g* (0*20 mole) of g-bromotoluene.

Sulfination was carried

out as described in the foregoing experiment*

A dense yellowish-

white solid separated out during the process*

hydrolysis was attempted

by pouring the reaction mixture into dilute acid and ice but this solid remained unaffected by the treatment*

I t was finally heated in

dilute hydrochloric acid, cooled, and then ether extracted*

This

ether layer was extracted with dilute base and the upper layer reserved (ether layer I).

The alkaline layer was acidified and the sulfinic

acid extracted with ether*

Evaporation of the extracts gave 5*U g*

of p-toluenesulfinic acid (1 % yield based on the g-bromotoluene and corrected for aliquots taken)*

This was oxidized as described in

the previous experiment to give 7 «U g* of mono-hydrated barium £-toluenesulfonate (16%based on the p-bromotoluene). Evaporation of (I) gave 8*0 g* of a yellow solid, insoluble in dilute base.

Recrystallization from petroleum ether-alcohol gave

a white solid, m.p. 92-3°•

This is the recorded melting point of

di-]>*tolylsulfoxide (2 0 ) and may have been formed as suggested by Burton and Davy (1). Ar.SOg.MgBr + Ar’MgBr ___»

ArSGAr1 *

(MgBr^O.

Another experiment similar to this was run but the results were no better.

I t was concluded that sulfination of aryllithium

compounds held more promise in the present research. Effect of Low Temperature on Sulfination of Aryllithium Compounds. Preparation of g-Toluenesulfinic Acid from £-Tolylllthium and Liquid

Sulfur Dioxide.

In a study on the preparation of some alkyl sul-

finates, Houlton and Tartar have reported that the reaction of Grignard reagents with sulfur dioxide proceeds more smoothly at -5 0 ° than at the commonly employed ice bath temperature (12)(15>). The present experiment was performed to ascertain i f any marked improvement in yield could be obtained using liquid sulfur dioxide and reduced reaction temperature in the sulfination of aryllithium compounds. Accordingly, p-tolyllithium was prepared as described previously (page 3 ) and the reaction mixture cooled to -5> 0° in a bath of Dry-Ice and trichloroetbylene.

Liquid sulfur dioxide

(70%excess over theory) was then added from a dropping funnel equipped with a cooling jacket.

Rapid stirring was maintained

throughout the reaction. After the addition of the sulfur dioxide, the reaction mixture was stirred at -5 0 ° for one hour and then allowed to come up to room temperature.

The mixture was hydrolyzed by pouring into ice and water.

The aqueous l^rer (actually alkaline due to the dissolution of excess lithium metal) was acidified and extracted with ether.

Evaporation

of the ether yielded p-toluenesulf inic acid in 69% yield based on g-bromotoluene« Since this result is practically identical with the results heretofore obtained at ice bath temperature, the use of greatly reduced reaction temperature is not warranted. Conversion of £- Chlorotoluene to Barium g-Toluenesulf onate via ^-Tolyllithium.

g-Tolyllithium was prepared in 56% yield from

p-chlorotoluene in the manner described (page 3

Sulfination in

7

the usual maimer followed by hydrolysis and extraction gave ^-toluenesulfinic acid in 3Q% yield (based on the aryl chloride)» Oxidation gave barium ^-toluenesulfonate in an overall, yield of 30^» Conversion of m — Bromotoluene to Barium m-Toluenesulfonate via m-Tolyllithium.

Starting with m — bromotoluene,

to ly lli thium

was prepared in 92 #5%yield in a manner analogous to that described (page 3)*

The sulfination step proceeded in Sh*3% yield and the

oxidation step proceeded in 65.5% yield.

The overall conversion of

m-bromotoluene to the mono— hydrated barium salt of m-toluenesulfonic acid was 33%. An authentic sample of m-toluenesulfonic acid was prepared ty oxidation of m-thiocresol according to the method of Holleman and Caland (11)*

An S-benzylthiuronium derivative was prepared from the

m-toluenesulf onate so obtained.

I t had an m.p* of l5l--l530.

The

melting point of the derivative prepared from the barium salt obtained in the present experiment melted at 155- 156° (see analysis below),

A mixture of the two melted at 153-155°. Anal. Calcd. for (OyHySCy^Ba.HgO:

Found:

Ba, 28.1$

Ba, 27.60$

HgO, 3.5.

Anal, of S-Benzylthiuronium Derivative.

^15% 8^2^2'

EgO, 3.62.

N* 8*28e

Found$

Calcd. for

8.30*

The low yield compared to the para isomer was believed to be due in part to the instability of the intermediate sulfinic acid (2 7 ). Conversion of o-Bromotoluene to Barium o-Toluenesulfonate via o-TolyHithium.

o-TolyHithium was prepared in the usual manner

from o-bromotoluene in practically quantitative yield.

I t was

8

sulfinated for one hour as described previously (page U) •

As an

added precaution to reduce the decomposition of the free sulfinic acid (2 6 ) 9 a ll solutions used for hydrolysis and extraction were kept at 0° and the product was kept out of contact with a ir as much as possible* obtained#

A 56% yield of crude o-toluenesulfinic acid was

Oxidation gave a 31% yield of barium o-toluenesulfonate

based on the aryl bromide*

The sample used for analysis was

recrystallized and dried at 77°, 2 mm. Anal* Calcd* for (CyHySO^gBa:

Ba, 28.65.

Found:

Ba, 28.65.

An S-benzylthiuronium derivative was prepared and recrystallized until the m.p* remained constant at 1 7 9 .5- 1 8 0 .5 ° after drying at 77° (2 ram.).

When mixed with the similar derivative of the para

isomer (m*p* 182°after drying) the melting point dropped to 160-5 °• Anal. Calcd.for

H, 8.28.

Found:

N, 8*33.

Inasmuch as the melting point of the o- derivative has been reported as 170° (1 8 ) i t was suspected that the barium sulfonate obtained in the present reaction might be the benzylsulfonate formed as a consequence of a hydrogen-metal interconversion* Consequently, sodium benzylëulfonate was prepared from benzyl chloride and aqueous sodium sulfite and derivatized with S— benzylthiuronium chloride.

The derivative melted at 163-5°

(after drying at 77°, 2 mm.). To prove the structure of the product obtained in the present experiment, an authentic sample of o-toluenesulfonic acid was prepared by oxidation of o-thiocresol according to the method of Holleman

9

and Caland (11). the product.

An S-benzylthiuronium. derivative was made from

After repeated recrystallizations i t melted at

180-1° (after drying at 77°, 2 mm.). When mixed with the derivative prepared in the present experiment no melting point depression was noted. Ferric o-Toluenesulfinate. o— Toluenesulfonate.

Its Oxidation to Potassium

Thomas has reported that ferric chloride is

an excellent precipitant for sulfinic acids and states that the ferric salts can be conveniently isolated (25).

In the present

experiment a technique is described (based upon this report) in which the isolation of the free sulfinic acid is obviated. After preparing o-tolylli thium in the usual manner the ether was evaporated in a stream of nitrogen.

A concentrated solution

of ferric chloride was added (79 g. of ferric chloride, 20 ml. of hydrochloric acid and U O Oml. of water) and the mixture was stirred and allowed to stand for several hours.

The ferric sulfinate

was filtered, washed with water and finally with alcohol. yield was obtained

(a s s u m in g

A 50$

the product obtained was the same

described by Thomas) . This salt was digested with dilute base for several hours and then oxidized with alkaline potassium permanganate solution keeping the temperature below 20°.

After filtratio n of manganese dioxide

and ferric hydroxide the filtra te was neutralized and evaporated to dryness.

Hot ethanol extraction of the dry salts gave a 3h%

yield (based on o-bromotoluene) of crude potassium o-toluenesulfonate.

10

This procedure for preparing the salt appeared to offer no advantages over the method described in the preceding experiment.

11

PART II THE PREPARATION OF SODIUMo-,

ANDp-n-

DODECYLBENZENESULFOM TES Introduction From the studies conducted in PART I i t ims known that the isomeric bromotoluenes could be converted to the corresponding toluenesulfonic acid salts by forming the lithium derivative, sulfinating i t , and oxidizing the sulfinic acid to the desired product*

The next step was to prepare the high molecular weight

analogs , p-bromo-n-dodecylbenzene, m-bromo-n-dodecylbenzene, and o-bromo— n-dodecylbenzene and then carry them through a similar sequence* I t was planned to prepare o-, m-, and p-bromolaurophenones by reacting n-hendecylcadmium with the appropriate bromobenzoyl chloride (2)*

These phenones could then be reduced to the corresponding

bromoalkylbenzenes* There were several methods available for reducing th is carbonyl group directly to a methylene group*

The

most common of these, however, were expected to result in some debromination of the ring*

I t was planned to try the Clemmensen

and the Wolff— Kishner techniques and compare the results •

The

reduction of compounds analogous to these were not recorded in the reviews presented in ^Organic Reactions11 (l6)(17 )•

If the debromina­

tion was found experimentally to be excessive, the corresponding chloroalkylbenzenes would be prepared and used in the synthesis*

12

Experimental Starting Materials•

-

(a)

n-Hendecyl bromide (obtained

from Columbia Organic Chemicals Co*, Inc., Columbia, S.C*) was purified by washing successively with cold concentrated sulfuric acid, sodium carbonate solution, and finally with water until the extracts were neutral*

After drying, the product was fractionated

through a Vigreux column (18*).

The fraction boiling at 102° at

It m m * was collected* (b)

£~Bromobenzoyl chloride, b.p*

127° (16-1 ? mm.), was

prepared in 92% yield fromg-bromobenzoic acid and thionyl chloride* (c)

m-Bromobenzoyl chloride, b.p.

122-3° (17 mm.) was

prepared in 93% yield from m-bromobenzoic acid and thionyl chloride. (d)

o-Bromobenzoyl chloride, b.p. 120-1° (15-16 ram. ) was

prepared in 95% yield from o-bromobenzoic acid and thionyl chloride. (e)

Thionyl chloride was specially purified by the method of

Fieser (5 )# (f )

Sodium permanganate solution was prepared by adding a

slight excess of sodium sulfate to a solution of barium permanganate and filtering. g-Bromolaurophenone (l).

This compound was prepared in

22-5UX yield in the manner described by Cason (2).

n-Hendecylmagnesium

bromide was prepared from 117 g* (0 .5 0 mole) of n-hendecyl bromide and 12.2 g. (0.50 mole) of magnesium in 300 ml. of ether.

The entire

reaction was carried out in an atmosphere of dry oxygen-free nitrogen.

13

The reaction mixture was cooled to 0° and j>0 ,U g. (0.2? mole) of anhydrous cadmium chloride added over a five minute interval.

After

the addition of 100 ml. more ether, the reaction mixture was refluxed until a negative Color Test I (7) was obtained (three hours). The ether was then removed and replaced with 300 ml. of benzene in the conventional manner.

To the stirred reaction mixture

was added 8?*8 g. (0 *U0 mole) of ^-bromobenzoyl chloride in 100 ml. of benzene over a one-half hour period. to maintain reflux.

Gentle heating was applied

After the final addition the mixture was

stirred and refluxed for three hours and then hydrolyzed by pouring into 10% sulfuric acid solution and ice.

The benzene layer was

separated and washed successively with

sodium hydroxide solution

and water.

The solvent was removed and the residue recrystallized

from petroleum ether (30-60°) to give 73 g# (5U %based on the acid chloride), m.p. 59-61°.

Further recrystallization brought the

melting point up to 62- 3°. Anal. Calcd.for C^gHg^OBr: Found:

C, 63*5;

H, 7.90;

C, 63#76;

H, 7*96;

Br, 23*57*

Br, 2^.2.

A 2 , U-dinitrophenylhydrazone, m.p. llU-50, was prepared. Anal. Calcd. for Cgl^iHjjOjjBr:

N, 10.79*

Reduction of p-Bromolaurophenone.

Found:

H, 10.80.

Wolff-Kishner vs. Clemmensen

Technique.

The Clemmensen technique was applied in the following

experiment.

p-Bromolaurophenone (17*0 g*, 0.05 mole), 1& 0 ml. of

toluene, 5 ml. of acetic acid and 18 ml. of water were mixed in a round-bottom flask.

To this was added U0 ml. of concentrated

Ht

hydrochloric acid and 23 g, (0 .3 5 g. atom) of zinc amalgamated with. 2*0 g* of mercuric chloride (6 )*

The mixture was refluxed for

seven hours and then the layers were separated.

The aqueous layer

gave a strong positive test for bromide ion with chlorine and carbon tetrachloride•

The toluene was evaporated from the organic layer

and the residue vacuum distilled.

The boiling range indicated a

mixture and none of the desired product was isolated. The Wolff"Kishner technique was applied in the following experiment.

To a mixture of 17 g. (0.05 mole) of j^bromolaurophenone*

5 0 ml. of diethylene glycol, and 6 g. of potassium hydroxide was added 6 g. of 85% hydrazine hydrate (13). at Hj.0° for four hours.

This mixture was refluxed

Water and hydrazine hydrate were then

removed until the temperature reached 195° and refluxing was continued at this temperature for five hours.

The mixture was poured into

water and ether extracted. The aqueous layer was acidified with nitric acid and boiled. A qualitative test with chlorine and carbon tetrachloride showed the presence of bromide ion.

Titration with silver nitrate indicated

bromide ion equivalent to 21%of the g-bromolaurophenone used. The solvent was removed from the ether layer and the residue tested for ketone with 2, U-dinitrophenylhydrazine. te st was obtained.

A strong positive

Distillation from a Claisen flask gave one fraction,

b.p. 200° (9 mm.), which did not give a ketone test and which was shown by subsequent analysis (shown in the next experiment) to be g-bromo-n-dodecylbenzene (3U*5% yield).

The fact that unreacted

ketone was present after the reduction was carried out, suggested

35

that the interval allowed for bydrazone formation should be prolonged before raising the temperature to obtain the reduced product.

The

difficulty in forming the bydrazone was shorn by another experiment. Loch and Stach have given the experimental conditions for the preparation of the bydrazone of £-chloroacetophenone (lU)«

"W hen

this procedure was applied to g— bromolaurophenone the yield of bydrazone was very low* I t was suspected that the debromination observed was the result of loss of bromine by the unreacted ketone at higher temperatures (190°)»

The bydrazone should decompose fairly readily

at this temperature to give the relatively inert £~bromo-n-dodecylbenzene. This was supported by the results of the next experiment in which special precautions were used to insure a higher yield of bydrazone before elevating the temperature.

The debromination dropped to

p~Bromo-n--bromolaurophenone was found in the aqueous layer* After removal of the ether, the organic residue was distilled from a Claisen flask to give 30.2 g* (60$) of g— brcmo-tn-dodecylbenzene, b.p. 190-1 ° (U mm. ), n£° 1.503UAnal. Calcd. for C^gHg^Brs Found:

Br, 2k»7s

C, 66*70;

Br, 2U*58s

C, 66*50;

H, 8*92*

H, 8 . 8 9 .

An Atteirpted Preparation of g-n-Dodecylphenylmagnesium. Bromide* g-Bromo-n-dodecylbenzene9 as prepared in the preceding experiment, reacted sluggishly with magnesium even though the usual devices, such as iodine, méthylmagnésium iodide, and prolonged refluxing were employed*

The ether used was carefully dried with calcium hydride

and added from a pipette to the reaction flask*

However, when

finely divided lithium was added to the reaction mixture (containing the magnesium and the unreacted aryl bromide) the contents became warm and a positive Color Test (7) was obtained within five minutes* In a separate experiment the yield of p-n-dodecylphenyllithium was found to be 75%. experiment*

This intermediate was sulfinated in the following

17

p-it-Dodecylbenzenesnlf Inic Acid (IU )>

To a 50O-ml. three-

neck flask equipped with a reflux condenser, stirre r, and a means of maintaining a positive pressure of pure nitrogen, was added 1*5 g* (0*22 g* atom) of finely divided lithium.

The la tte r had been pounded

out into thin strips and then cut with a scissors to fa ll directly into the flask*

Over a one-half hour period, 29*2 g* (0*09 mole)

of g-bromo-n-dodecylbenzene in 120 ml. of dry ether was added to the lithium, after which the mixture was stirred and refluxed for one hour.

In a separate experiment, the yield of the aryllithium

intermediate was found to be

by direct titration.

The flask was then immersed in an ice bath and dry sulfur dioxide was passed through the stirred solution for one hour.

An

additional 1 0 0 ml* of dry ether was added during the sulfination* Preliminary experimentation indicated that hydrolysis and extraction resulted in emulsions very difficult to break*

Consequently the

reaction mixture was centrifuged and the ether layer decanted from the residue.

The latter was washed twice with ether by centrifugation

and subsequently dislodged from the centrifuge bottle with dilute acid.

This formed a suspension which was extracted with ether.

The

la tte r was dried with Drierite, filtered, and evaporated to give a 63% yield of crude £-n-dodecylbenaenesulfinic acid (m.p. U9-5l°) • The product, recrystallized twice from petroleum ether, was à white powder, m.p. 5h“S ° 9 which slowly turned yellow on standing. Anal* Calcd* for Found:

C, 70*0;

H, 9*6U*

C, 6 9 .6 8 ;

H, 9.67*

18

Soditan £-n~DodecyXbenzenesu3-fonate (IV)♦

To 17*0 g*

(0.055 mole) of g-n— dodecylbenzenesulfinic acid was added 200 ml. of 2%sodium hydroxide solution and a slight excess of a 1$ sodium, permanganate solution (peroxide oxidation as used on the lower homologs caused excessive foaming).

The temperature was

maintained between 35-liO° during the oxidation.

After standing

overnight excess permanganate was reduced with sodium sulfite and the mixture was heated to boiling and filtered hot.

The filtra te

was neutralized with sulfuric acid and evaporated to dryness.

Hot

ethanol extraction of the dry salts gave 1 3 .U g. (70$) of sodium n-dodecylbenzenesulfonate. Anal. Calcd. for

N#, 6.60.

Foundt

Hà, 6.56

The product yielded an S-benzylthiuronium, salt, m.p. 95-7°. However, after drying at 77°, 2 mm., for forty-eight hours prior to analysis, the melting point was found to be 117- 8° after softening a t 100°. Anal. Calcd. for

:

N, 5.69*

Founds

N, 5*68.

The product also yielded a £-toluid±ne salt, m.p. 138-139.5°, after drying at 77°, 2 mm. Anal. Calcd. for C25H 39SO3N: m-Bromolaurophenone.

N, 3.23.

Found:

N, 3*26.

This compound was prepared from,

m-bromobenzoyl chloride and di-n-hendecylcadmium as described for (I). The crude ketone was obtained by distillation from a Claisen flask in a nitrogen atmosphere.

Those fractions (b.p. 170-200°, 1-2 mm.)

which gave a positive ketone test were combined for further

19

purification*

The product was separated from a persistent contaminant

n-docosane, by dissolution in glacial acetic acid and filtratio n of the insoluble hydrocarbon. and ether extracted*

The filtra te was diluted with water

After washing the ether extracts successively

with 2% sodium hydroxide solution and water, the ether layer was dried and evaporated.

The product was further purified by fractional

recrystallization from 2 :1 methanol-acetone to give a 20%yield of product, m.p, 25-30°.

The sample submitted for analysis melted at

29-30°, Anal, Calcd. for G^HgyOBr: Found:

C, 63.3;

0, 63*76;

H, 7*96.

H, 7*89>

The ketone yielded an orange 2,U-dinitrophenylbydrazone, m.p. 103-U° after drying at 77°> 2 mm. Anal. Calcd. for C2kH3i% 0l1Br: m-Bromo-n-dodecylbenzene.

N, 10.79*

Found:

N, 10.89.

To a mixture of 33*U g* (0.10 mole)

of m-bromolaurophenone, lU g. of sodium hydroxide, and 135 ml. of diethylene glycol, was added 32 g. of 85% hydrazine hydrate. reduction was carried out as described for (II ).

The

Bromide ion

equivalent to 3%of the bromophenone was found in the aqueous layer. A 60%yield of crude m-bromo-n-dodecylbenzene, b.p. 182-192°, 3 mm., was obtained.

Over 80% of the product boiled between 188-192°,

3 mm., nj}0 1.50UU. Anal. Calcd, for CiQHgpBr: Found:

C, 6 6 . 8 ;

H, 9*05;

G, 66.50;

H, 8.92;

Br, 2^.58.

Br, 21*.52.

m-n-Dodecylbenzensulfinic Acid.

This compound was prepared

in U U %yield from 1 5 .0 g. (0 .0l*.6 mole) of m-bromo-n-dodecylbenzene

20

and 0 .7 7 g. (0 .1 1 g. atom) of lithium in the manner described for (III).

The yield of the aryllithium intermediate was 7%*

The

product after two recrystallizations from petroleum ether was a white powder, m.p. 63-U0* which became yellow on standing. Anal. Founds

Calcd. for O^gHgpSOgH: C, 6 9 .68 ;

C, 6 9 .80;

H, 9*67.

H, 9 .6 8 .

Sodium m-n-Dodecylbenzenesulfonate.

This compound was

prepared in 80$ yield from 5 .7 g. (0 .0 1 8 mole) of m-n-dodecylbenzene­ sulfinic acid as described for (IV). Anal. Calcd. for

Eà, 6.60.

Founds

Ha, 6.62.

The product yielded an S-benzylthiuronium salt, m.p. 97-8°, after drying at 77°, 2 mm. Anal. Calcd. for Cg^Hj^HgO^Sg:

5.69.

Founds

N, 5.66.

A £-toluidine salt was likewise prepared, m.p. 103-1^°, after drying at 77°, 2 mm. Anal. Calcd. for C25H39SO3N: H, 3.23.

Found:

H, 3.31.

Preparation of Sodium m-n-Dodecylbenzenesulfonate frcan m-Bromo-n-dodecylbenzene via a Halogen-Metal Interconversion Reaction. The interconversion technique followed was essentially that of Gilman and Woods (9). To 12.0 g. (0.037 mole) of m-bromo-n-dodecylbenzene dissolved in UOml, of dry ether was added with stirring over a one hour period 0.037 mole of n-butyllithium in 215 ml. of dry ether.

The

reaction flask was immersed in an ice bath before the addition of the

n-butylHthium..

After the final addition the mixture was stirred

at ice bath temperature for two hours and then allowed to stand one hour at room temperature.

At this point Gilman test I (7)

was strong and Gilman test XI was weak (orange color) (8). Sulfination and oxidation of the sulfinate were carried out in the usual manner.

The product (lU$ yield)was shown to be

identical with that prepared in the foregoing experiment by a mixed melting point of the S-benzylthiuronium salts. o-Bromolaurophenone.

This compound was prepared from

0-bromobenzoyl chloride and di-n-hendecylcadmium as described for (I) The crude ketone was dissolved in 2si methanoltacetone, cooled and filtered to remove a small amount of n-docosane.

The filtra te

was evaporated and the residue fractionated through a l5,f Vigreux column under nitrogen to give a 33$ yield of product, b.p. 187-189.5° 1-r2 mm.,

1.5116*

Anal. Calcd. for C^gHgyOBrs Founds

C, 63.90;

H, 7.98;

C, 63.76;

H, 7*96;

Br, 23.57.

Br, 23*32.

To obtain a good yield of the 2, ^-dinitr ophenylhydrazone i t was necessary to reflux a mixture of the bromophenone and 2,1*.dinitrophenylhydrazine in an acid-ethanol solution overnight. Cooling deposited yellow crystals which were dissolved in pentane and filtered to remove unreacted reagent. yellow crystals, m.p. 68-9°.

Cooling the filtra te gave

The product was purified chromato-

graphically to remove an otherwise persistent impurity and dried at 1*0°, 1-2 mm., m.p. 70-1°.

22

Anag, Calcd* for

N, 10.79.

o-Bromo-n^dodecylbenzene.

Founds

N, 10*81,

To a mixture of Ü>3.h g* (0.16 mole)

of o-bromolaurophenonej 21 g. of sodium hydroxide^ and 205 ml, of diethylene glycol -was added 50 g* of 85% hydrazine hydrate. reduction 'mas carried out as described for (II).

The

Bromide ion

equivalent to 15% of the bromophenone was found in the aqueous layer* The crude product was fractionated through a l5" Vigreux column under nitrogen to give 26*5 g* (52%) of o-bromo-n-dodecylbenzene, b.p. 17U-60, 2 mm., nfj° 1.5060. Anal* Calcd* for C^gHg^Brs Founds

C, 66.65;

H, 8.72;

C, 66.50;

H, 8.92;

Br, 21*.58.

Br, 2l*.3.

Sodium o-n-Dodecylbenzenesulfonate.

To 1.0 g. (.11* g. atom)

of finely divided lithium was added 17 g. (0.052 mole) of o-bromo-ndodecylbenzene in 80 ml. of dry ether.

In a separate experiment the

yield of the aryllithium intermediate was found to be 90%.

Sulfination

in the usual manner failed to precipitate the desired lithium sulfinate* However when a small sample was withdrawn from the reaction mixture and the solvent and sulfur dioxide removed under nitrogen, the residue was found to be neutral on hydrolysis.

With another sample treated

similarly a negative Color Test I was observed (7). The diethyl ether was evaporated from the reaction mixture and replaced by petroleum ether, 30-60°.

A white solid which proved to

be lithium bromide settled out immediately and was filtered.

The

filtra te slowly became turbid on standing at room temperature and a brown gelatinous solid collected after two hours.

This crude

lithium, sulfinate, separated and washed by centrifugation, weighed 6 .7 g. (1*1%) after drying. Four grams of this product was oxidized with sodium perman­ ganate as described for (IV) to give 1.7 g. (38% based on the lithium sulfinate) of crude sodium o— rt-dodecylbenzensulfonate.

The product

yielded an S-benzylthiuronium salt, m.p. 100-1°, after drying at 77°, 2 mm. A n a l, C alcd . f o r 02d%0^2^3^2"

5 .6 9 .

Found:

N, 5 .6 9 #

When mixed with the related derivative of the meta isomer (m.p. 97- 8°) the mixture melted at 85-7°.

2k

PART HI THE PREPARATION OF SODIUM£-LAUROYLBENZENESUIFONATE. REDUCTION TO SODIUMp-^DODECTEBENZENESULFONATE Introduction The preparation of ]>-bromolaurophenone has been described in PART II (page 12).

Rosemrand has reported the preparation of

sodium g-toluenesulf onate from p-bromotoluene and aqueous sodium sulfite at elevated temperature and pressure (23),

The presence

of the carbongrl group in the para position in ^-bromolaurophenone ■was expected to increase the reactivity of the halogen atom toward aqueous sodium sulfite (2U),

This has been supported experimentally

using p— bromolaurophenone and p-bromo-n-dodecylbenzene in separate tria ls .

Only the former reacted with sodium sulfite.

Reduction of

the product, sodium p-lauroylbenzenesulfonate, via the Clemmensen technique gave sodium £-n~dodecylbenzenesulfonate,

The reduction

of ketosulfonates by this method is believed to be novel (1 6 ). Experimental Preparation of Sodium £-Lauroylbenzenesulfonate.

In a

1— 1. iron autoclave were placed 20.0 g. (0.059 mole) of p-bromolaurophenone (see page 12), 50 g. of sodium sulfite, 2.0 g. of cupric sulfate, and 500 ml. of water.

The autoclave was closed and the

contents rocked at 180° for four days followed by rocking for two

25

days at 220°*

The contents were emptied, filtered, and the insoluble

material was extracted with ether.

Evaporation of these extracts

gave the unreacted p-bromolaurophenone. The et her— insoluble material was dissolved in hot ethanol and filtered while hot.

Cooling the filtra te deposited the product.

I t was recrystallized from ethanol to give 6.1 g. (28.5%) of sodium g-lauroylbenzenesulf onate• Anal. Calcd. for G^gl^QSO^ÎÏLas

6.35.

Found:

Eâ, 6*27.

Results of the present experiment (No* 36) as well as other results are summarized in Table I.

An S-benzylthiur onium derivative

was prepared and dried at 77°, 2 mm., m.p. 166-7°. Anal. Calcd. for

N, 5.53*

Found:

N, 5.5U.

Table I Preparation of Sodium jD-Lauroylbenzenesulfonate

Expt. No. 19 29 30 36

WT. of charge materials (g.) Time cl8H 27OBr Ha2S03 HgO CuSOj^ (hrs. ) 2.0

59

20 20

20 100

5o 50

200

5oo 5oo 500

1.0 2.0 2.0 2.0

ZtO 2k

96 lU t

Temp. % 0C. Yield*

190 200 180 180-220

% Conversion**

28

59

k2 hh

28 1.6 19 29

•«Based on ketone consumed. 5H$Based on ketone charged. An Attempted Preparation of Sodium g-n-Dodecylbenzenesulf onate from p-Bromo-n-dodecylbenzene and Sodium Sulfi t e.

g-Bromo-n-

dodecylbenzene (1.3 g.> 0.00U mole) was placed in a Carius tube with

26

3*3 g* of sodium sulfite, 0.5 g* of cupric sulfate and 35 mL* of water.

The tube was sealed and heated for twelve hours at 175°•

The temperature was then raised to 205° and maintained there for twenty-four hours*

The tube was not agitated during the heating period.

None of the desired sodium, g-n-dodecylbenzenesulfonate was isolated. Reduction of Sodium g-Lauroylbenzenesulfonate via the Clemmensen Technique.

Sodium g-lauroylbenz enesulfonate (3.0 g*, 0.008 mole)

was added to a flask containing 10.0 g. of amalgamated zinc, 35 mL. of concentrated hydrochloric acid, 5 ml. of glacial acetic acid and 15 ml. of water.

The mixture was refluxed for three hours and then an

additional 10 ml. of concentrated hydrochloric acid was added. Refluxing was continued for a total of fifteen hours. After cooling the reaction mixture a gelatinous solid was isolated; i t gave a positive test for zinc.

To convert this product

to the sodium salt i t was digested with sodium carbonate and the precipitated basic zinc carbonate filtered.

After neutralisation of

the filtra te , i t was evaporated to dryness.

Extraction of the

residue with hot ethanol yielded 0.3 g. of product from which an S-benzylthiuronium derivative was prepared*

After drying at 77°

and 2 mm. i t melted at 117-9° following a preliminary softening at about 112°.

The S-benzylthiuronium. derivative of the starting

keto acid melted at 166-7° (page 25) whereas the reduced compound, sodium p-n-dodecylbenzenesulfonate, prepared independently gave a derivative which melted at 117-8° (see page 18).

The melting point

27

of the latter showed no significant depression when mixed with the derivative prepared in the present experiment*

The preliminary

softening mentioned above may have been due to an impurity of some unreduced ketoacid present before derivatizing • A second reduction was performed as described from 5*0 g* (0*0lU mole) of sodium g-lauroylbenzenesulf onate, 20 g* of amalgamated zinc, 25 ml* of concentrated hydrochloric add, 20 ml* of water and 5 ml* of glacial acetic acid.

After refluxing for twenty hours and

adding 5-10 ml* of concentrated hydrochloric acid every 3-U hours, the mixture was decanted from the zinc and evaporated under an air je t.

The residue was dissolved in hot ethanol, cooled to 10°, and

the insoluble zinc sulfonate separated by centrifugation (zinc chloride is soluble 100 g. per 100 ml* of alcohol at 13°)•

I t was

then converted to the sodium salt with 3% sodium carbonate solution as described in the previous experiment*

The yield of crude

sodium £-n-dodecylbenzenesulf onate was 2*0 g. (U0$) * The S-benzylthiuronium derivative after repeated recrystallizatio n melted at 113°• When mixed with an authentic sample of S-benzylthiur onium g-n-dodecylbenzenesulfonate the m.p* was IIU-II80. I t was concluded that the product obtained by the Clemmensen reduction was probably the desired sodium g-n-dodecylbenzenesulfonate but its purity was questionable.

28

PART IV ALKYLA-TIONEXPERIMENTS WITH n-DQDECYL £-TOLDENESULFOI'IA.TE Introduc tion Gopenhaver et al have reported the preparation of p-bromoàlkylbenzenes by the reaction of ^-bromophenyImagnesium bromide with various alkyl esters of

toluenesuifoni c acid (It.)*

I t was planned

to prepare this Grignard reagent and alkylate i t with n-dodecyl id - toluenesulfonate

to prepare g-bromo-n-dodecylbenzene• Althou^i

the latter had already been prepared in PART II (page 15) i t was of interest to see i f the yield could be improved by another method.

Experimental An Attempted Preparation of £-Bromo-n-dodecylbenzene. of £-Di-n-dodecylbenzene.

Isolation

n-Dodecyl-gytoluenesulfonate was prepared

as described by Marvel and Sekera (19).

Instead of preparing the

Grignard reagent f ir s t and thai adding the ester, another approach was adopted in order to avoid the production o^ p-p1-dibromobipheryl by coupling of the Grignard (21).

A small amount of this by-product

would be difficult to separate from the desired p-bromo-n-dodecylbenzene. Accordingly, 1*9 g* (0*08 mole) of magnesium was added to a three-neck flask and a mixture of 19*2 g* (0*08 mole) of jo-dibromobenzene and 5h*h g* (0.16 mole) of n-dodecyl ^-toluenesulfonate in 150 ml* of dry ether was added to the magnesium from a separatory

funnel.

Refluxing was spontaneous*

After the final addition,

stirring at reflux-temperature was continued for four hours at which time a negative Color Test I (7) for the Grignard reagent was obtained*

The mixture was then hydrolysed by pouring into ice

and dilute acid.

The ether layer was separated, filtered, dried,

and then heated on a steam bath to remove the ether*

The residue

was distilled at 10 m m * pressure. None of the desired product was obtained*

However,

p-di-n-dodecylbenzene was isolated from the reaction mixture indicating that £-bromo-n-dodecyibenzene had been present, but i t formed a Grignard intermediate which was further alkylated to the dialkyl compound.

The latte r had an m.p* of U7~U9°*

Anal. Caicd. for C^qH^: Foundï

C, 8 6 .Î45

G, 86.975

H, 13.03.

H, 13*8.

Under proper conditions, i t is probable that this reaction would afford a convenient general method for the preparation of p-di-n- alkylbenzenes. Preparation of £-Bromo-n-dodecylbenzene.

p-Bromophenyl-

magnesium bromide was prepared in the usual manner from. £-dibromobenzene and magnesium turnings.

In order to minimize the coupling

reaction in this run, a relatively large volume of ether was used. n-Dodecyl £-toluenesulf onate was then added at a rate sufficient to maintain reflux.

After stirring and ref luring for an additional

twelve hours, the mixture was hydrolyzed by pouring into ice and 2.0% hydrochloric acid* solvent evaporated.

The ether layer was separated, dried and the

30

Distillation at 5-6 mm. yielded a compound boiling at the correct temperature for p-bromo-n-dodecylbenzene (I8I4.0) but decompo­ sition in the still-p o t occurred when this fraction was being collected and the product was considerably contaminated.

Since the yield

was obviously low the product was not redistilled. Some Attempted Inter-molecular Alkylations.

n-Dodecyl

p-bromobenzenesulf onate was prepared from p-bromobenzenesulf onyl chloride and 1-dodecanol in the manner described in “Organic Synthesis1 * (19)*

I t was hoped that the ring bromide could be

converted to the Grignard intermediate, and that the latter in turn would be inter-molecularly alkylated by the dodecyl group of the ester,

hydrolysis of the reaction mixture should then yield

p-n-dodecylbenzenesulfonic acid. MgBr

Thus:

Br

G-ioHoc:

Br

so3c12H 25

S03c12h25

SO^MgBr

However, a ll attempts to carry out the desired reaction failed* Refluxing the ester in ethyl ether with magnesium did not cause any reaction to take place*

The solvent was changed to butyl ether but

refluxing s t i l l did not produce the desired reaction.

31

SUMMAHT

le

Barium o - s m-, and £-toluenesulionates have been prepared

by a novel method*

This consisted in preparing the appropriate

aryllithium compound (e*g. p-tolyllithium) sulfinating i t , and then oxidizing the sulf ini c acid to the desired product*

Heretofore, the

Grignard reagent has been sulfinated in this type of synthesis*

The

use of aryllithium. compounds, besides giving an intermediate of increased reactivity, has several other advantages. can be converted to the corresponding sulfonate*

An aryl chloride

Thus, g-chlorotoluene

was converted to barium g-toluenesulfonatej this conversion is impossible or very difficult via the Grignard reagent.

By the use

of metalation and interchange reactions with n-butyllithium, difficultly obtainable sulfinates can be prepared* "W hen p-tolylmagnesium bromide was sulfinated the yield of g-toluenesulfinic acid was found to be 1S>% whereas sulfination of g— tolyllithium gave a 68% yield of the same acid, 2*

o— , ut-, and g-Bromolaurophenones have been prepared from

di-n-hendecylcadmium and the appropriate bromobenzoyl chloride. These phenones have been reduced to the corresponding -, m~, and p-bromo-n-dodecylbenzenes "by the Wolff-Kishner method*

The la tte r

was found to give better results than the Clemmensen method.

32

These high molecular weight aryl bromides were then converted to the corresponding sodium o-, m-, and jo-n-dodecylbenzenesulfonates by the same sequence described ibr the low molecular weight analogs* Derivatives have been prepared for the final products and for many of the intermediates* 3.

Sodium g-lauroylbenzenesulfonate has been prepared in

29%yield from g-bromolaurophenone and aqueous sodium sulfite at elevated temperature and pressure*

The product has been reduced

via the Clemmensen technique but the sodium £~n-dodecylbenzene­ sulfonate obtained was impure and the yield was low, U* In an attempt to prepare p-bromo— n-dodecylbenzene by alkylation of |>-bromophenylmagneslum bromide with n-dodecyl p-toluenesulfonate, p-di— n-dodecylbenzene was isolated*

Other

alkylation experiments with this ester have been described.

BIBLIOGRAPHY )

Burton and Davy* J. Chem> Soc.j, 528 (I9I48),

)

Cason, J. Am. Chem. Soc«a 68, 20?8 (19U6).

)

Chambers and Watt, J. Org. Chem., 6, 376 (19U1)*

) Gopenhaver, Roy, and Marvel, J, Am. Chem» Soc., 57, 1311 (1935) ) Fieser, "Experiments in Organic Chemistry", D* C. Heath and Co., Hew,York, H.Y., I9I1I , p. 381. )

Fieser et al, J. Am. Chem. Boo. ^ 70, 3197 (191+8).

)

Gilman and Schulze, ibid., U?, 2002 (1925).

)

Gilman and Swiss, ibid., 62, l81j.7 (191+0).

)

Gilman and Woods, ibid., 66, 1981 (19UU)•

) Hann, ibid., 57, 2166 (1935). ) Holleman and Caland, Ber., 2501+ (19H). ) Houlton and Tartar, J. Am. Chem. Soc., 60, 51+1+ (1938). ) Buang-Minlon, ibid., 68, 21+87 (191+6). (11+) Loch and Stach, Ber., 77, 293 (191+1+). )

Marvel and Johnson, J. Org. Chem., 13, 822 (191+8).

)

"Organic Reactions", Vol. I, John Wiley and Sons, HewYork, H.Y., 191+2, p. 155.

)

"Organic Reactions", Vol. IV, John Wiley and Sons, New York, N.Y., 191+8, p. 378.

) "Organic Reagents for Organic Analysis", Hopkin and Williams Research Laboratory, Chemical Publishing Co.,Inc., Brooklyn, N.Y., 191+6, p. 163. )

"Organic Synthesis", Vol. 20, John Wiley and Sons, Hew York, H.Y., 192+0, p. 50. _

) Parker, Ber., 23, 181& 1+ (I89O).

3lt

(21)

Quelet, BtOJL, soc, chim., bX» 933 (1927).

(22)

Rosenheim and Singer, Ber., 37, 2152 (1901$.)•

(23)

Rosenmund, ibid., 5U, U38 (1921).

(2U)

Suter, “The Organic Chemistry of Sulfur”, John Wilqy and Sons, Rew York, M.Y., 19UUa p. 362.

(25)

Thomas, J. Chem. Soc.a 953 3U2 (1909).

(26)

Troeger and Voigtlander-Tetzner, J. prakt. Chem.3 5Ü, 513 (IB9 6 ).

(27)

Troger and m ile, ibid.,, 71, 201 (1905).

V IT A

Joseph P. lyons was born November 27, 1920, at Wappingers Falls, BUY.

He entered Fordham University, NewYork, N.X., in

September, 1937, and was awarded the Bachelor of Science degree in June, 191*1.

In March, 19U6, he entered Purdue University Chemistry

Department and received the Master of Science degree in February, 19U8» He was admitted to the degree of Doctor of Philosophy in June, 1950.

He is a member cf Phi Lambda Upsilon.