The Preparation and Properties of o- and p-n-Dodecyltoluene

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The Preparation and Properties of o- and p-n-Dodecyltoluene

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PURDUE UNIVERSITY

T H IS IS TO C E R T IF Y TH A T T H E T H E S IS P R E P A R E D U N D E R MY S U P E R V I S I O N

WALTER EDWARD KRAMER_______________________________

BY

ENTiTLPH

THE PREPARATION AND PROHSRTIES OF o — AND

_______

____________DOiJECYLTDLME______________ ____________ ____ _______________

C O M P L IE S W ITH T H E U N IV E R S IT Y R E G U L A T IO N S O N G R A D U A T IO N T H E S E S

A N D IS A P P R O V E D B Y M E A S F U L F IL L IN G T H IS P A R T O F T H E R E Q U IR E M E N T S

FOR THE DEG REE OF

MASTER OF SCIENCE

^ ^ ^ j ® a t o F E s s o R IN C h a r g e

H

ead o p

S

chool or

o p

Th

D epartm

e s is

ent

TO T H E L IB R A R IA N :T H IS T H E S IS IS N O T TO B E R E G A R D E D A S C O N F ID E N T IA L .

PBOFESSOB Hf CBAKOE

KEGUSTBAB POBM 10—5 .4 4 — IM

THE PREPARATION AND PROPERTIES OF Or AND £-n-DODECILTOLUEKE

A T hesis Submitted to the F aculty of Purdue U n iversity

Walter Edward Kramer In P a r tia l F u lfillm e n t o f the Requirements fo r the Degree of Master o f Science June, 194 s

ProQuest N um ber: 27708583

All rights reserved INFORMATION TO ALL USERS The q u a lity of this re p ro d u c tio n is d e p e n d e n t u p o n the q u a lity of the co p y su b m itte d . In the unlikely e v e n t that the a u th o r did not send a c o m p le te m a n u scrip t and there are missing p a g e s, these will be n o te d . Also, if m a te ria l had to be re m o v e d , a n o te will in d ic a te the d e le tio n .

uest P roQ uest 27708583 Published by ProQuest LLO (2019). C o p y rig h t of the Dissertation is held by the A uthor. All rights reserved. This work is p ro te cte d a g a in s t u n a u th o rize d co p yin g under Title 17, United States C o d e M icroform Edition © ProQuest LLO. ProQuest LLO. 789 East Eisenhower Parkway P.Q. Box 1346 Ann Arbor, Ml 4 8 1 0 6 - 1346

ACKNOWLEDGEMENT The author w ishes to express h is sin cere thanks and ap p reciation to Dr, E. T, McBee and to Dr. W. E« Truce fo r th e ir u n fa ilin g cou rtesy, su g g estio n s, and a s sis ta n c e throughout the course o f t h is research .

TABLE OF CONTENTS Page ABSTRACT..........................................................................................*

i

INTRODUCTION..................................................................................

1

DISCUSSION..................................

3

EXPERIMENTAL 1.

The Attempted Preparation o f Lauraldehyde by the Rosenmund Reduction o f Lauroyl Chlarride # 6 a.

Preparation o f the Rosenmund C a ta ly st

b.

Preparation o f C a ta ly st P o i s o n ..................... 6

c. 2.

Attempted Reduction o f Lauroyl Chloride to Lauraldehyde .....................

6

7

a.

7

Preparation o f the Copper-Silver

C a ta ly st

Oxidation o f the Lauryl A lcohol to L au rald eh yd e..............................................................9

Preparation o f o - and p-n-D odecyltoluene . . . a.

4.

6

Preparation o f Lauraldehyde by the Air Oxi­ dation o f Lauryl A lcohol . . . . . . . . .

b. 3.

. .

Method fo r the D etectio n o f Organomagnesium H alides . . ..................

10 10

b.

S yn th esis of o- and _p-n-Dodecyltoluene , . 11

c.

The Clenmiensen Reduction o f o - and p-Me thyllaurophenone . »

Preparation o f 2-Phenyldodecane

. 13

. . . . . . . 1 3

SUMMARY.................................................................................................. 15 BIBLIOGRAPHY..........................................................................................16

THE PREPARATION AND PROPERTIES OF o - AND jp-n-DODECYLTOLUENE

by W, E , Kramer,* E* T, McBee, and W, E , Truce Purdue U n iv ersity , West L a fa y ette, Indiana AN ABSTRACT

In trodu ction In recen t y ea rs, various alk ylbenzenesulfonates^ and numerous 1,

S u ter, "Organic Chemistry o f S u lfu r Compounds," John W iley and Sons, I n c ., New York, N. I . , 1942, p. 206,

r e la te d products have been patented as w etting and su r fa c e -a c tiv e a g e n ts. The purpose o f t h is research was to sy n th esize new alkylbenzenes whose su lfo n a tes might be o f value as su rfa c e -a c tiv e a g en ts.

The sy n th eses

were chosen to minimize com plications due to rearrangements and oth er sid e r e a c tio n s. 1.

The two methods

employed

The Grignard reagent o f

a h a lid e

were as fo llo w s: was trea ted with a ketone to

y ie ld a high-mol e cu lar-w eight a lc o h o l upon h y d r o ly sis.

The r e s u lt in g

alc o h o l was deh^idrated to the o le f in by h eatin g w ith potassium hydrogen s u lf a t e .

The saturated hydrocarbon was obtained by reduction o f the

o le f i n w ith hydrogen and Raney n ic k e l, 2,

The Grignard reagent o f a given bromotoluene was trea ted w ith 2 anhydrous cadmium ch lo r id e to form the ditolylcadm ium . The correspond2,

Gilman and Nelson, Rec. tr a v . chlm. . 55. 518 (1 9 3 6 ). *An a b str a ct o f the th e s is by W, E, Kramer, Submitted to the F acu lty

o f Purdue U n iversity in p a r tia l fu lfillm e n t o f the requirem ents fo r the degree o f Master o f S cien ce in June, 1948.

11

in g high-m olecular-w eight ketone was produced by tr e a tin g the d i t o l y l cadmium with la u ro y l ch lo r id e. carbon by the Clemmensen method. 3.

The ketone \fas reduced to the hydro3

Adams, e t a l . , "Organic R eactions," V ol. I , John W iley and Sons, I n c ., New York, N. Y ., 1942, p. 155.

D iscu ssion The purpose o f t h is research p ro ject was to prepare 2-phenyldodecane,^ a known compound, and the isom eric n -d od ecyltolu en es, h ith e r to 4.

Schmidt and Grosser, 3 e r . . 7 5 . 829-33 (1 9 4 2 ).

unprepared.

The d esired p u rity o f the products was such as to y ie ld

s a tis fa c to r y u lt r a - v io le t absorption sp ectra with r esp ect to known, pure dialk yIb en zen es.

Two methods o f sy n th esis were devised fo r the prepara­

tio n o f the n -d od ecyltolu en es. The f i r s t one required lauraldehyde and th e proposed r e a c tio n s are li s t e d below. a)

c)

CH^C/H/MgBr ^OMgBr CH^C^H^MgBr f C11 H23 CHO ------^ CH3 C^H^CHC22H23 ^OMgBr CH3C5H^CHC^3^H23 — MgCl Br

d)

CH3 C^H^H0 HC22H23

e)

CH3 G^H^CH «

b)

CHGC^HÆr + Mg - dry .etheg^

CH3 C^H/^CH « ^%^6^4 ^12^25

Because lauraldehyde was not a v a ila b le a t the s t a r t o f t h is research , two methods o f sy n th esis were attem pted.

The f i r s t method, the Rosenmund

red u ction o f la u ro y l ch lo r id e, follow ed the procedure used fo r th e reduc­ tio n o f naphthoyl ch lo rid e to naphthaldehyde.^

No aldehyde was obtained

iii

5*

Organic S y n th e sis, V ol. XXI, John W iley and Sons, I n c ., New York, N, Y ., 1941, p . 84.

and i t was assumed th a t an ir r e v e r s ib le polym erization had taken p la ce as had been p rev io u sly observed in the sy n th e sis o f analogous aldehydes by t h is method.^ 6,

E n g lish and V e lic k , J .

Chem. S o c. . 67. 1413 (1 9 4 5 ).

The second method attem pted was the a ir o x id a tio n o f la u r y l a lc o h o l in the presence o f a co p p er-silv er catalyst."^ 7.

The y ie ld o f aldehyde was

Davies and Hodgson, J , Chem. Soc. . 282 (1 9 4 3 ).

so low th a t t h is method was abandoned because s u f f i c ie n t la u r y l a lc o h o l was not a v a ila b le to prepare the amount o f lauraldehyde necessary fo r a l l the sy n th eses. The Grignard reagents o f the bromo tolu en es were prepared and trea ted w ith anhydrous cadmium ch lorid e to give the corresponding organocadmium compounds*^

Treatment o f the organo cadmiums with la u ro y l ch lo rid e and

subsequent h y d ro ly sis y ie ld e d the interm ediate k eton es.

These ketones

were reduced to the n-d odecyltolu en es by the Clemmensen method,^

The

r ea c tio n s fo r t h is sy n th e sis are g iven below. a)

CH^G^H^r + Mg

CH^C^H^MgBr

b)

2 CH3 C^H^M^r a CdCl^ ------». (CH3 C6 H^)2 Cd f 2MgClBr

c)

(CH3 C^H^)2 Gd » 2 C11H23 COCI

d)

CH3C^^C0C33H23

». 2 CH3 C^E^C0 C^^H2 3 '^ CdCl2

HCl ^ CH3C^H^Ci2H25 Zn—Hg

2-Phenyldodecane was prepared using the procedure o f Schmidt and G rosser,^

Acetophenonewas combined ivith the Grignard reagent o f n -d ecy l

IV

ch lo r id e to y ie ld a te r tia r y a lc o h o l on h y d r o ly sis.

The sa tu ra ted hydro­

carbon was obtained by dehydration o f the a lco h o l w ith potassium hydrc^en s u lfa t e and red u ction o f the r e s u lt in g o le f in with hydrogen and Raney n ick el*

The rea ctio n s used are l i s t e d below*

a)

CjflHalCl t Mg

CioH21 %C1

b)

CioH2 iI%Cl r C^H5COCH3 ----- *-

^CH3 - C - 0 - MgCl ^10^21

C£^5 - G - 0 - %C1

CH3 I - C - OH

^10’^ 21

G10^21

003

c)

d)

/CHo G6H5 - C - OH

.CH3 c^H5 - G = CHC^H^^

^10^21 e)

C^H5 -

/CH3 C=

XCH3 - CHCigH^^

Experimental The Rosenmund c a ta ly s t was prepared according to the d ir e c tio n s in Houben-Weyl*^ 8,

To a suspension o f 82 g , o f barium s u lfa te and 7 g . o f

Houben-Weyl, "Die Methodm der Organischen Chemie," D r itte Aufleige, George Thieme, V erlag, L eip zig , 1923, p . 500,

palladium ch lo rid e in 1,600 g , o f hot water, 4 ml* o f 40^ formaldehyde so lu tio n was added.

The mixture was made weakly a lk a lin e t o litm u s by

the ad d itio n o f a 10^so lu tio n

o f sodium hydroxide.

A fter th e suspension

was b o ile d fo r one hour, the supernatant liq u id was decanted and

the

c a ta ly s t was washed fr e e o f ex cess a lk a li .

The c a ta ly s t was d ried in an

Abderhalden vacuum p i s t o l , p u lv erized , and stored in an a ir - t i g h t b o ttle * The c a ta ly s t poison was made by heatin g 6 g. o f q u in o lin e with 1 g, o f su lfu r fo r one hour*^ i^ le n e

The poison was d ilu te d w ith 70 m l. o f anhydrous

.

The d ir e c tio n s used for the preparation o f naphthaldehyde from naphthoyl chloride^were fo llo w ed fo r the preparation o f lauraldehyde from i t s acid chloride*

The rea c tio n f la s k , p a r t ia lly immersed in an o i l bath,

was charged w ith 220 g , ( 1 . 03- mole) o f la u ro y l ch lo rid e, 19 g. o f c a t a ly s t , 600 m l, o f anhydrous x ylen e, and 1 ,8 ml. o f c a ta ly s t p oison .

The r e a c t­

ants were maintained a t 140 - 50° w hile hydrogen was bubbled through a t a rapid r a t e .

The hydrogen ch lorid e evolved was absorbed in a s o lu tio n o f

40 g, ( 1 ,0 mole) o f sodium hydroxide to which was added a few drops o f

phenolphthalein s o lu tio n ,

When the phenoIphthalein was d eco lo rized , the

rea ctio n was considered complete,

A period o f e ig h t hours was required

to complete t h is red u ction . A fter the c a ta ly s t was removed by f i l t r a t i o n , the mixture was con­ cen trated by removal o f the xylen e under vacuum.

A ll attem pts to is o la t e

lauraldehyde by vacuum d i s t i l l a t i o n or by the form ation o f a b i s u l f i t e ad d ition product f a il e d .

Tests with T o lien ' s reagent on samples o f the

untreated concentrate f a ile d to rev e a l the presence o f any aldehyde. Ten mesh pumice stone was used to prepare the co p p er-silv er c a ta ly s t for the a ir oxid ation o f la u r y l a lc o h o l to lauraldehyde*"^

The granulated

pumice stone was b o ile d in a so lu tio n o f concentrated n i t r i c a c id fo r n in ety minutes and then washed free o f a c id .

The washed stone was soaked

in a 10^ s o lu tio n o f copper n itr a te fbr four hours.

The copper so lu tio n

was decanted and a 10^ so lu tio n o f sodium hydroxide was added u n t il the

vi

r e s u ltin g so lu tio n remained a lk a lin e to litm u s.

When the stone turned

b lack , the s o lu tio n was poured o f f and th e m a teria l was washed fr e e o f excess a lk a li . The stone was dried fo r tw elve hours a t 110^ and th e copper oxide on i t was converted to m e ta llic copper by reduction with hydrogen a t 400 ° in a Cariu® furnace.

The copperized stone was cooled to room temperature

in an atmosphere o f hydrogen.

The cooled stone was soaked fo r an hour

in an ammonical so lu tio n o f 10^ s ilv e r n itr a te , washed fr e e o f e x ce ss s ilv e r s o lu tio n , and dried in an atmosphere o f hydrogen a t 110^,

The

c a ta ly s t was rejuvenated sev era l tim es by rep eating the l a s t two t r e a t ­ ments* The la u ry l a lco h o l was o x id ized to lauraldehyde in a clo sed system made e n tir e ly o f Pyrex g la s s .

The pressure in the system was 100 mm.

The

alcoh o l was introduced a t the ra te o f 5 ml, per minute and th e a ir a t

500

ml. per m inute.

The a ir was regu lated by a flowm eter.

The a ir -a lc o h o l

mixture passed through the co p p er-silv er c a ta ly s t where the o x id a tio n took p la ce .

The c a ta ly s t was maintained a t 360° by a Carius furnace.

Three

hours were required fo r 700 g , (3 .8 6 moles) o f a lco h o l to be o x id ized a t the above ra te o f fe e d .

The lauraldehjnie was is o la t e d from the o x id a tio n

products by the b i s u lf it e a d d ition method and 70 g , (0 ,3 8 mole) o f hyde was recovered.

ald e­

This represented a y ie ld o f 10^ o f th eory.

The d e te c tio n o f organomagnesium h a lid e required two reagen ts,^ 9,

Gilman and î-larple, Rec. tr a v . chim. . 55, 133 (1936).

The f i r s t reagent was made by d is s o lv in g 1 g , o f Michler^s Ketonein 100 m l, o f anhydrous benzene and th e second reagent was made by d is s o lv ir ^

v il

a sm all c r y s ta l o f io d in e in 100 ml. o f g la c ia l a c e t ic a c id .

The t e s t

was performed by combining 1 m l, o f ketone so lu tio n w ith 1 ml, o f r ea c tio n mixture in a clea n , dry t e s t tube.

A fter vigorous shaking, 20 drops o f

water was added very ca u tio u sly from a medicine dropper. o f the iod in e so lu tio n was added.

Then, 5-10 drops

Upon vigorous a g ita tio n , a l l the ma­

t e r i a ls d isso lv e d and two clea r la y ers r e s u lte d , A blu e-green co lo ra tio n in e ith e r la y er was a p o s itiv e t e s t fo r the organomagnesium h a lid e .

When a l l the magnesium was d isp la ced by cadmium,

the color o f the t e s t s o lu tio n was lig h t y ello w . The procedures used to prepare o - and g-n -dod ecyltolu en e were id e n t i2 c a l and follow ed th e d ir e c tio n s given by Gilman and Nelson fo r the prepa­ r a tio n o f high-mole cu lar-w eight ketones by the use o f organo cadmium com­ pounds,

The G ri^ ard reagents o f q- and p- bromo toluene were made by

tr e a tin g 342 g , ( 2 ,0 moles) o f the bromides with 48 g, ( 2 ,0 çioles) o f magnesium in dry eth er.

During the ad d ition o f cadmium ch lo r id e , d ried

by fu sio n o f the s a l t , the rea c tio n fla s k was immersed in an ic e bath. The ad d ition o f 336 g. (2 .0 moles) o f cadmium ch lo rid e required two hours. Anhydrous eth er was added from time to time to keep the rea cta n ts in a f lu id co n d itio n .

Test samples were withdrawn every f if t e e n m inutes.

Thirty minutes a f t e r the f in a l a d d ition o f cadmium ch lo rid e, the t e s t s fo r the organomagnesium compound were n egative and the mixture was then g en tly heated on a steam bath fo r an hour to in sure com pleteness o f r e ­ a c tio n . The rea c tio n mixture was cooled in an i c e - s a l t bath to -5 ° and hydrolyzed by the cautious ad d ition o f cracked i c e .

S u f f ic ie n t co ld ,

d ilu te s u lfu r ic acid was then added to d is s o lv e a l l the s a lt s formed.

v iii

The eth er la y er was drawn o f f and washed w ith water and d ilu t e sodium hydroxide s o lu tio n . The ketones were p u r ifie d by vacuum d i s t i l l a t i o n from a C laisen f la s k .

The pure p-methyllaurophenone was a w h ite, c r y s t a llin e s o lid and

melted a t 4 1 -42°,

I t s b o ilin g p oin t was 194-195° (1 mm, u n c o r r ,).

ortho ketone was a y ello w , v isco u s liq u id w ith a fragrant odor. b o ilin g p o in t o f the ortho ketone was 162° ( 1 mm, u n co rr,).

The

The

Two-hundred

f i f t y grams ( 0 ,9 1 mole) o f the para ketone and 220 g. (0 ,8 1 mole) o f the ortho ketone were produced. theory, r e s p e c tiv e ly .

They represented y ie ld s o f 45^ and 40^ o f

The 2,4-dinitrophenylhydrazone o f the para ketone

was prepared and m elted a t 118° ( c o r r .) ,

The ortho d eriv a tiv e could

not be prepared. The method used to reduce th ese ketones to th e ir corresponding hydrocarbons follow ed the d ir e c tio n s given fo r the reduction o f analogous ketones by the Clemmensen

m e t h o d ,3

A xylene so lu tio n con tain in g 250 g ,

( 0 .9 1 mole) o f p-methyllaurophenone was poured onto amalgamated zin c h alf-co v ered by concentrated hydrochloric a cid and allowed to r e flu x fo r nine hours.

In the corresponding experiment, 210 g, (0 ,7 7 mole) o f

q-methyllaurophenone was used.

The hydrocarbons obtained from t h is re­

duction were r e c t if ie d in a tw o -fo o t, s p ir a l wire column a t reduced p ressu re.

One-hundred tw enty-four grams (0 .4 8 mole) o f p -n -d o d ecy l-

toluene and 100 g, (0 .3 9 mole) o f q -n -d cd ecyltolu en e were obtained. y ie ld s were 50^ and 48^ o f theory, r e s p e c tiv e ly .

The

The p |iy s ic a l coniants

fo r the para compound were, b .p , 154 - 156 ° (1 mm. uncorr.) and

1 . 4820 .

The constants fo r the ortho isomer were, b .p . I 6 l ° ( l mm. uncorr.) and 1.4815. The method fo r making 2-phenyldodecane fo llo w ed the d ir e c tio n s given

ix by Schm idt and G ro sser,'^

The G rignard re a g e n t of n -d e c y l c h lo rid e was

p rep ared by t r e a tin g 353

g. (2 ,0 mole) o f n -d e c y l c h lo rid e w ith IS g.

(2 .0 moles) o f magnesium

in dry eth er.

from the a d d ition o f 240

g. (2 .0 moles) o f acetophenone to the Grignard

reagent.

A te r tia r y a lc o h o l was produced

The hydrocarbon was obtained from the a lc o h o l by dehydration

o’f the a lc o h o l with potassium hydrogen s u lfa te and subsequent reduction o f the r e s u ltin g o le f in with hydrogen and Raney n ic k e l.

The impure pro­

duct was te ste d with B aeyer's reagent to d e te c t the presence o f unsatura­ tio n ,

The 2-phenyldodecane was r e c t if ie d in a tw o-foot s p ir a l wire column

a t reduced pressure and 175 g. (0 ,7 1 mole) o f product was obtained. y ie ld was 75"^ o f theory.

The

The p h y sica l constants fo r the compound were,

b .p . 143° (2 mm. uncorr.) and

01.4849.

Summary The preparation o f lauraldehyde by the Rosenmund reduction o f la u ro y l ch lorid e was attem pted,

No lauraldehyde was obtained by t h is method,

Lauraldehyde was produced by the a ir -o x id a tio n o f la u ry l a lco h o l in the presence o f a co p p er-silv er c a ta ly s t. q and q-n-D odecyltoluene were prepared by the Clemmensen reduction o f the corresponding k eton es.

The ketones were produced by the rea c tio n

o f lau ro y l ch lorid e with the proper ditolylcadmium compound.

The 2 ,4 -d i­

nitrophenylhydrazone o f q-methylaurophenone was prepared. 2-Phenyldodecane was prepared by the reduction o f 2-phenyldodecene

with hydrogen and Raney n ic k e l.

The o le f in was obtained by dehydration

o f the corresponding te r tia r y a lc o h o l.

INTRODUCTION In recen t y ea rs, the value o f d etergents has been recognized*

As

a r e s u lt , a lk y lb e n z e n e s u lf o n a t e a n d numerous r e la te d products have been patented as w ettin g and s u r fa c e -a c tiv e a g en ts.

The products ob­

tain ed by the su lfo n a tio n are g en era lly complex m ixtu res.

The hydro­

carbon interm ediates are prepared by the condensation o f o le f in s or a lk y l h a lid e s w ith benzene in the presence o f such condensing agents as aluminum ch lo rid e, boron t r if lu o r id e , and s u lf u r ic a c id . In view o f the in crea sin g demand for s u r fa c e -a c tiv e a g en ts, attem pts were made to prepare new hydrocarbons which could be used as d etergen ts in term ed iates.

Therefore, the purpose o f th is research was to sy n th esize

such hydrocarbons and to co rrela te th e ir stru ctu re w ith th e ir su rfa cea c tiv e p r o p e r tie s.

A ccordingly, the preparation o f pure monoalkylbenzenes

and dialkyIbenzenes was undertaken. There are many methods for the preparation o f high-m olecular-w eight hydrocarbons.

The methods employed were chosen to minimize com plications

due to rearrangements or other sid e r e a c tio n s .

The two general methods

o f sy n th esis used were as fo llo w s; 1,

The Grignard reagent o f a h a lid e was trea ted with an a v a ila b le

ketone or aldehyde.

The interm ediate a lco h o l from th is r ea c tio n was

dehydrated by h eatin g w ith potassium hydrogen s u lf a t e to the o le f i n . The o le f in was reduced to the saturated hydrocarbon with hydrogen and Raney n ic k e l, 2.

The Grignard reagents o f th e bromotoluenes were prepared and

treated w ith anhydrous cadmium ch lorid e to form the ditolylcadm ium s^/.

2.

High-molecu la r-w eig h t ketones were produced by combining the d i t o l y l cadmiums w ith high-mol e cular-w eight acid c h lo r id e s .

These ketones were

reduced to the corresponding hydrocarbons by the Clemmensen method.2^

3.

DISCUSSION The purpose o f t h is research p ro ject was to prepare 2-phenyldodecane, a known compound,^ and th e isom eric n -d od ecyltolu en es, h ith e r ­ to unprepared.

The d esired p u rity o f th e products was such as to y ie ld

s a tis fa c to r y u lt r a - v io le t absorption sp ectra w ith r e sp e c t to known, pure d ialk y lb en zen es. For t h is reason, the F ried el-C ra fts rea c tio n was not used sin ce the mixture o f high-mol e cu lar-w eight compounds would be d i f f i c u l t to r e c t i f y . The rea c tio n between an a lk y l h a lid e and an a r y l magnesium h a lid e was another p o s s ib ilit y * ArMgX + RX ----- -- Ar-R * MgX^ However, th is rea ctio n i s mainly lim ited to those a lk y l halide^which con­ ta in a r e a c tiv e halogen.

In a d d itio n , three hydrocarbons in stea d o f on ly

one would be produced during the course o f t h is r e a c tio n .

The three

p o s s i b i l i t i e s are Ar-Ar, Ar-R, and R-R^-- '^ -^ and the y ie ld o f the d esired compounds would be low. For th e preparation o f the n -d od ecyltolu en es, two methods were de­ v is e d ,

The f i r s t one required lauraldehyde and the proposed rea c tio n s

are l i s t e d below, a)

CH3C6H^Br . Mg

.

CHjC^H^MgBr H I

b)

CH^C^H^MgBr + CnHg^CHO

CH^C^H^C - 0 - MgBr ^11^23

c)

CH^C^H^C - 0 - MgBr -S PÂ,,» CH^C^H^CROEC^g^Hg^ ^11^23

MgClBr

4.

d)

CH3C^H^CHDHC]^2%3

e)

CH^C^H^CE = GHCioHqi

*'

= CHC]^oH2^

S ince lanralddiyde was not a v a ila b le a t the s t a r t o f the research , attem pts were made to prepare i t .

About one-thousand grams o f the a ld e­

hyde was needed to carry out a l l the sy n th eses.

The f i r s t method tr ie d

was the Rosenmund red u ction o f la u ro y l ch lo rid e according to the d ire c­ tio n s used fo r th e preparation o f naphthaldehyde^.

No Jauraldehyde was

is o la te d , presumably because o f an ir r e v e r s ib le p olym erization .

Such a

sid e rea ctio n had been observed p reviou sly-^ . The other method fo r the preparation o f lauraldehyde involved the a ir oxid a tio n o f la u r y l a lco h o l to the aldehyde in the presence o f a catalyst^ ^ .

Air and a lco h o l vapors were passed over a co p p er-silv er

c a ta ly s t, mounted on granulated pumice stone, a t 360°,

The y ie ld from

th is rea ctio n was so low, th a t u n less large q u a n titie s o f the a lc o h o l were a v a ila b le , s u f f ic ie n t amounts o f the aldehyde could not be produced in t h is manner.

Since only seven-hundred grams o f pure la u r y l a lc o h o l

was on hand, the a ir -o x id a tio n method to ob tain the aldehyde was a lso abandoned.

This n e c e ssita te d a method o f preparing th e n -d odecyltolu en es

which would not require lauraldehyde as an in term ed ia te. The Grignard reagents o f the t o l y l bromides were prepared and t r e a t ­ ed w ith anhydrous cadmium ch lorid e to y ie ld the corresponding d i t o l y l cadmiums^A^ When la u ro y l ch lorid e was added to the rea ctio n m ixture, the interm ediate methyllaurophenones were produced.

The lowered r e a c t iv it y

o f the organo cadmium compounds prevented the form ation o f any te r t ia r y alco h o l which would have been the case had the organomagnesium compounds been u sed .

These ketones were reduced to th e hydrocarbons by th e Clemmen-

5.

sen m ethod^.

The rea c tio n s are given below.

a)

CH^C^H^Br + Mg

GH^C^E^MgBr

b)

2 CH3C^H4MgBr ♦ CdCl^

c)

(GH^G^H^)2Cd + 2G11H23 COGI -------

d)

CH3C6H^C0 CuC 23

------------------

*

2MgClBr

2CH^C^H^G0 C22 H23+ GdClq

2-Phenyldodecane was syn th esized according to the procedure used by Schmidt and G r o sse r ^ ,

Acetophenone was added to the Grignard reagent

o f n -d ecy l ch lorid e to form a te r t ia r y a lc o h o l.

The t e r t ia r y a lc o h o l

was dehydrated to the o le f in by heating w ith potassium hydrogen s u lf a t e . The saturated hydrocarbon was obtained from the o le f in by red u ction in an Adams Reductor w ith hydrogen and Raney n ic k e l.

The rea ctio n s used

are given below, a)

C10H21 CI i- Mg

CiflHjiMgCl CH3

b)

C2oH2 iMgCl + C^H^C0CH3 -----

- C - OMgCl ^10% 1

CH3

CHq