The Addition of ’Bromine-Chloride’ to Olefins

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The Addition of ’Bromine-Chloride’ to Olefins

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SHE ADDISIOH OF

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SO GUBFXNft

w aw

**

John W* Dong I I I

A t h e s i s s u b m itte d i n p a r t i a l f u l f i l l m e n t o f t h e r e q u i r e ­ m ents f o r th e d e g re e o f D o c to r o f P h ilo s o p h y *’ i n th e D epartm ent o f C hem istry i n t h e G rad u ate C o lle g e o f th e S ta te U n iv e r s ity o f Iowa,

February 1950

ProQuest Number: 10666177

All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is d e p e n d en t upon the quality o f the co p y submitted. In the unlikely even t that the author did not send a co m p lete manuscript and there are missing p a g es, th ese will b e noted. Also, if material had to b e rem oved, a note will indicate the deletion.

uest ProQuest 10666177 Published by ProQuest LLC (2017). Copyright o f the Dissertation is held by th e Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States C o d e Microform Edition © ProQuest LLC. ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106 - 1346

Y v s^ o C o p .'S L

AOJOSOWlEjBOHBHl*

ffee anther desires to express deep appreciation to Br* Hefcert S. Bookies for h is in terest and assistanoe

H

throaghoat th is in vestigation.

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f A B ll- O f o m n m u

fage

tin # MU PROB1*2*11 # * * « 4 # * * ■ # * * ♦ # ■

SRfM&twXflK * * * * #. «- *■ * * ♦ » # % t *

*♦ * 4

fla t l o i i i i t # com plex « * » * * Bromine C h lo rid e. . # # « « • » « * « * * • « R ea c tio n s o f N-Bromo&eetamid e 4 * • • * * » » M i o c r w i t i '.* * # * 4 4 ^ * * * * * * *

♦ *

s b

14 £4.

.* ^ * ss ♦

Preparation o f .,$«*Br©#©acetai8iae (6S)*

3.

49

«« « » 49

P r e p a r a tio n o f H ^ o iilo r e a e e ta s iie (6$) ** # * 61 P r e p a r a tio n o f Anhydrous s ta n n ic d&Lortdei 62) 52

Pf epa rat ion Preparation Preparation Preparation

of of of of

tra&#*StiXbeoe (64)* « * * * . alpha^then^loinnamie Aeid (63) ei#'*$tilh eae * « « * . » • • « l^Bromo^2-*CMioro'«Ithane., * . •

62 62 62 62

fr e p a r a tio n o f , styrenehroTO ahlori& e (l-P h en y l*

I * o n 0 r0 *2 ^ir## 0 «than») hy ad dition o f T* i r » l a e C h lo rid e ^ t o s ty r e n e * ♦ S t r u c t u r e P ro o f o f S ty re n e B rom ocfeloride. * . P r e p a r a tio n o f a l p h a - c h l o r c s t y r e a e {S i ) . O o n re ra io n o f a lp h a ■*e h l or© sty r one to- a e e te p h a a o n e .

*

* OEBr - CH - G0% IcBgOH

e Ig - CHBr - CHBr * OgHg fill

OgHg * OHBr - GBGCHg - 0§S§ IX

B a r t l e t t a n t k a r t e l l also - p o in te d o u t t h a t th e k i n e t i c s w ere I n e o n n ig te a t w ith any m echanism a t t r i b u t i n g p r i n c i p a l a c t i v i t y t o p o s i t i v e brom ine Io n o r t o m eth y l h y p o b ro m ite c a ta l y s e d by a c id *

However*, th e y added " a lth o u g h we re g a rd

By* m

tie tio o *

iff

h® Ig n o re d t h a t f r e e hy d ro g en

1 $ M i n s o l u t i o n a r e a l s o * f i a t i o n # and i t may d e r e lo p t h a t f o r p u rp o s e # o f c l a s s i f i c a t i o n * p o s i t i r e h a lo g e n io n s

may h e |n s i a® u se fu l a f l o t i o n a s .fre e p r o t o n s 11 ( 115* $h e tw e * # te p m e h a a te m o f th e h a lo g e n a d d i t i o n was f u r t h e r f e r i f l e d . By B a r t l e t t and f a r f c e l l {IE}#

fh e y re *

p o r te d t h a t th e a d d i t i o n o f aq u eo u s Brom ine o r c h l o r in e t o d im e th y l n a X e a te o r d im e th y l fu m a ra te Io n pro d u ced a s t h e s o le p r o d u c t one o f two s te r e o is o m e r ! s a lp h a * h & le * h e ta * la e * to n e s (XI I#

trader th e c o n d itio n # o f th e r e a c tio n * n e i t h e r

B XI

111

XIII

th e dihrem© compound {XII) nor the bromeby&rln (XIII) could he concerted t o th e lactone* therefore* n eith er could he an interm ediate*

thus* a iwo*step reaction in volvin g an io n ic

interm ediate (XI?) was c le a r ly indicated*

§

Is rils tt

m i f a r b e l l m a in ta in e d t h a t 'b o th s te r e o is o m e r s w ere

o b ta in e d b e c a u se t h e a c t i v e n e g a tiv e o a r b e x y la te Io n a t * tack ed t h e carbon!um io n b e fo r e atari® e q u ilib r iu m to o k p la c e * H e b e r ts and K im b all ( i s ) p o in te d o ttt t h a t a ©&r~ boalusi io n in te r m e d ia te

(M) would r e s u lt i n f r e e r o t a t i o n

a b o u t t h e e*?hen*eajfben bond w hich would le a d t o a m ix tu re

f

Js

Mgm Q m Q m %■

If o f e g a a l amounte o f th e e l * f&ey a g r e e w ith B a r t l e t t

m i tm m h a le g e a a tio n p ro d u c ts#

m i f a r h e l l in th a t f r e e r o ta tio n

a b e u t th e o& rbeo*eafben bond was n o t t o be expected*. a c c o u n t f o r t h i s l a c k o f r o ta tio n * H eberts



m i K im b all p ro *

posed th e o p a l in bromouium io n in te rm ed ia te*

fh e y contended

t h a t wi t i e i n h e r e n t l y im p ro b a b le t h a t a c a rb o n atom ca r ry in g o n ly aim e le c t r o n s sh o u ld be cap ab le o f e x i s t e n c e in th e c l o s e v i c i n i t y o f th e u n sh a re d e l e c t r o n s o f bromine* (13)»

$h eae w o rk e rs p ro p o sed t h a t a c o o r d in a te l i n k i s

form ed by t h e s h a r in g o f one o f t h e e le c t r o n p a i r s o f th e h a lo g e n w ith th e u n o ccu p ied o r b i t a l o f th e c a rb o n (IV I)* Another p o s s ib le s t r u c t u r e o f th e io n w ould p la c e th e p o s i t i v e c h a rg e on th e h alogen*

f h i s was e x p la in e d by th e

10

E

jori

%

£ r+

l

m u

a ssu m p tio n t h a t X+ l s i s o e l e e t r o n l e w ith a member o f th e o x y g ta fa m ily ana sh o u ld show a v a le n c e o f tw o , t h a t i s , i t sh o u ld form a s t r u c t u r e of the e th y le n e o x id e ty p e (X H I)* a h e l e c t r o n i c p o i n t o f view C1TI) and {mil) a r e i d e n t i c a l and t h e a c t u a l s t r u c t u r e i s p ro b a b ly b etw een th e two*

S in c e t h e two c a rb o n s I n e i t h e r p ro p o sed s t r u c t u r e

e r e jo in e d by a s i n g l e b o o t and a h a lo g e n b rid g e * f r e e ro~ t a t i o n w ould n o t be e x p e cte d * I f * however* l a r l y ch a rg e d g ro u p s (

and

{ or E

and B^) a r e sim i

coo") t h e r e may be s u f f i c i e n t

r e p u ls i o n b etw een them t o overcom e th e r e s t r a i n i n g f o r c e o f t h e d o u b le lin k a g e * and r o t a t i o n t o th e o p p o s ite o o n fig u * r a t i o n may ta k e p la c e b e f o r e th e second s te p o f th e r e a c t i o n o ccu rs* I n th e seco n d ste p * th e new atom { X * OH 9 e tc # ) Would ap p ro ac h one o f th e c a rb o n atom s from th e s id e o p p o s ite t o th e h a lo g e n atom a lr e a d y p r e s e n t*

T h is would

alw a y s le a d t o tran @ ~ & d d itio n e x c e p t i n th e e a ^ e w here th e r e a r e two l i k e ch a rg e d g ro u p s in th e c i e p o s itio n *

In o r d e r

11

i c a c c o u n t f o r t h e o b se rv e d p r o d u c t (Allli) th e second s te p

o

hr

***

v

AVI-*

H XTXII ■teat he accom panied w ith a ffald en In v e rs io n * T h is m echanism e x p la in e d th e e x i s t i n g d a ta on a d ­ d i t i o n s o f h a lo g e n s t o e t h y l e n i c d o u b le bonds* o h lo rlm

Bromine and

add l a r g e l y tra m s t o m a le ie and fu.ma.rla a c id s a s

th e th e o r y p re d ic t® *

t h e a d d i t i o n o f brom ine and c h lo r in e

t o fum & rate io n l a a g a in p re d o m in a n tly tr a m s , b u t a d d i tio n t o m a le a te io n i s @1® b e c a u se o f th e n e g a tiv e ly c h a rg e d , cl® c a r b o x y la te Iona* The c y c l i c in te r m e d ia te e a s i l y e x p la in s th e d i f f e r e n t d ib ro m id e s o b ta in e d from el® and t r a o s s t l l b e n e and account® f o r th e fo rm a tio n ©f th e a lp h a -b & lo -b e ta -l& o to n e s (XX)* The r e s u l t s o f num erous i n v e s t i g a t i o n s (1 4 ,1 5 1 6 ,1 8 ) by W ln s te in and h ia c o -w o rk e rs have se rv e d t o con­ f irm th e c y c l i c brooxmlu® io n I n te r m e d i a te ,

W in ste in and

L ucas by s tu d y in g d i s t r i b u t i o n m easurem ents d e m o n stra te d th e e x i s t e n c e o f c o o r d in a tio n com plexes which, s i l v e r io n form s

IS w ith o l e f i n s (14)*

fh e y proposed th e fo llo w in g str u c tu r e fo r

t h e © iby [email protected] M e* sllv © r Io n com plex {111}*

)o -o I

A$

)o = o < kg'

xa M m m m ® ® in v o lv in g t h e two h o n ied form© a n t th© unbonded form;:: i s h e l l w e t t o a c c o u n t f o r th e s t a b i l i t y o f t h e mm p le x * Mow th a t t h i s p o s it iv e io n h a s te e n shown t o he p r e s e n t 'in aq u eo u s e o l a ti o n * th e e x i s te n c e o f t h e p o s i t i v e brom ine o l e f i n com plex seem s more re a so n a b le th a n fo rm erly * W In s ts in a n t lu a& s (14} b e l i e v e t h a t t h e p o s s i b i l i t y o f re so n a n o e among f o u r form s* XX* XXX* XXII* XX III c o n t r i ­ b u te s t o th e s t a b i l i t y o f t h e p o s i t i v e h ro m o -e le fin complex*

/\

/

$*■- y

y

B)*

\/

Q

Bj?

A

+0 /\

XX

XXX

B r—

A JkXlL 11

t h e f i r s t form.* XX* probably c o n tr ib u te s most* and th e l a s t form* .XXIII* l e a s t b ecau se o f th e s t a b i l i s i n g e f f e c t a r is in g from bond form ation between bromine and carbon*

13 W i& stein ana L ucas r e p o r te d t h a t d l* e r y th r o ~ 3 fejtoM*£*fcut&iiol (XXIf) ana d l^ th re o * 3 -b ro m o -& * b u ta n o l (XXYI) whan t? * a te & w ith hydr&toromta a c id w ere c o n v e rte d t o m u o**E, S^dlhrosAOtfUtane i'MXf) and &!*£* 3*dihr©iiohut&n© (XX.fiI) r e s p e c t i v e l y (1 4 )*

I n h a th c a s e s , th e y o b se rv e d co m p lete

r e t e n t i o n o f c o n f i g u r a t i o n unaccom panied by ra e e m is a tio n * 01 Br

Br Br

i i

eHr e - c - c i g

ja r*

i i

B3e - c - c - c B g

H 8

H I

XXI? OH H I I CH_— 0 —C—OH

^5

iT3r.

Z ~aa^*

^ [ H Br

Br H I I 0K=— 0— C—OH

B |

|

H

&m

Z

Br

xm i

2 h le r e te n t io n o f ec m fig u ra tio n was ex p la in ed By '.Sinsteln and Luoas

ae B ein g due t c a o y o lie broooniam io n in t e r ­

m ediate (XX) and a d oable Walden in v e r s io n ; C— OH I

-c

A

x X

,) o

, - » c - 0H+ I

B r -C A

B

* Hg ° B r O

—i#->

) f - Br Br-C -2 &

l

G ^ ^ B r -q

a

A

and

c-

A

XX f h i e mechanism was co n firm ed (16) by th e o b s e r ­ v a t i o n t h a t co m p lete l o s s o f o p t i c a l a c t i v i t y was o b ta in e d

14 when o p t i c a l l y a c t i v e e r y th r o * o r thre0*-3~br©mo~2*'but&A©l w&« t r e a t e d w ith h y d ro b ro m ie a c id t o form *&fbrom©butane* S im ila r ly # D neas and Gould (16) p ic tu r e d t h e eon** v e r s io n o f ( )*three*& "©hl©ro*2*butanol (XXYXIX) t o bl**B# $«& iahlorehutan* (XIX) m

p ro c e e d in g v ia a ehloronium io n

in te r m e d ia te (XXIX), and a d o u b le Walden in v e rs io n # 1

01

H

01

01*

OH— C—C -C H S0C1£) CH=— o -< ls-r.H 3 | | S * » | | * 01 H O H

%.x t iix

+

aoa c l y ^ n ^ a

o

*/

OS

x

B

I

*0- 3 - 0 1

am C l“

01 H

I

CH_— C —G—CH

3

ani

H Cl

01

CH— C - C - C H „ 3

I

|

3

Cl H XX%

Bromine C h lorid e $he p r e s e n c e o f brom ine c h l o r i d e in s o l u t i o n h as b een th e s u b j e c t o f much c o n tro v e rs y and many in v e s t i g a t i o n s , At t h e b e g in n in g o f t h i s c e n tu r y , e v id e n c e b ased on m e ltin g and b o i l i n g p o in t d a ta s tr o n g ly d e n ie d t h e e x is te n c e o f t h i s compound#

D u rin g t h e n e x t few y e a r s some I n v e s t i g a t o r s

p r e p a r e d compounds which# th e y b e lie v e d # w ere due t o t h e i n te r m e d ia te fo rm a tio n o f brom ine c h lo rid e #

More c o n c lu s iv e

W l& cac* was f u r n is h e d l a t e r by s p e c tr o s c o p i c and e l e c t r o * ehem ie& t jaeceu rcm en ts#

F in a lly # p ro d u c t a n a ly s is # , v a p o r

ptcmcjig’c and ■d e n s i t y d a t a and h tm e tio s t u d i e s d e f i n i t e l y in** . A l e a t e t t h a t b ro m in e c h l o r i d e can e x i s t i n s o l u t i o n a t l e a s t t o a l i m i t e d e x te n t# B a la rd f i r s t r e p o r te d t h e fo rm a tio n o f brom ine /

c h l o r i d e by t h e d i r e c t c o m b in a tio n o f brom ine and c h l o r in e

(80)* A few y e a r s l a t e r # Loewig mad® a d o u b tf u l c la im t h a t b ro m in e c h l o r i d e penbabydjm t® c o u ld be p re p a re d (21)* I n 1863* E c to n b tia t r e a t e d ' an aq u eo u s s o l u t i o n o f brom ine and c h l o r i n e w ith f i n e l y d iv id e d p h o sp h o ru s* s i n e and i r o n and a t t r i b u t e d th e p r o d u c tio n o f t h e r e s p e c tiv e b ro m id es and c h l o r i t e s t o t h e ’.in te r m e d ia te f o rm a tio n o f hr©* mine o h lo r it o ( M U

k d i l u t e sm lfu rou s a cid s o lu t io n o f bromine and c h lo r in e was a n a ly sed by

Bommann (23) i n order to prove

th e s t r u c t u r e o f bromine c h lo r id e # t h a t i t was a d ia to m ic m olecule*

He d o u b tfu lly concluded Bornemaim a ls o reported

t h a t c r y s t a l l i n e bromine c h lo r id e Aeaabydrate was formed by t r e a t in g bromine c h lo r id e w ith w ater a t tem peratures below Q°# Good e v id e n c e f o r th e e x is t e n c e o f bromine c h lo r id e was o f fe r e d in 1883 by James (24)*

E th ylen e bromochlorid©

was prepared in 68 t o 70# y i e l d by p a ss in g e th y le n e in to an

fegM eM e o la t io n o f bromine# i*ydr©ohl©ria a e id and c h lo r in e a t «. te m p tjftts tre o f

Jam es s u g g e s te d t h a t t h i s r a t h e r

h i # y i e l d wag k m t o t h e in te r m e d ia te fo rm a tio n o f brom ine e h lo ri& e * t h e m ® o f brom ine c h l o r i d e m

a ehem ia& l r e a g e n t

feeeitw* m m * a t t e n t i o n f o r t h e n e x t t M r t r * # e v e a y e a rs# f h i e w as p r o b a b ly t h e t o th e e v id e n c e ( d is c u s s e d below) p r e ­ s e n te d I n 190? by I**bea& (2#) and K s r e te n s (2 ? ) w hich in d i c a t e d t h a t su c h a compound d id n o t e x i s t*

Benewea

I n t e r e s t I n brom ine c h l o r i d e was a ro u se d in 1920 by B e le p in e and T ill® (2 9 )# w ork o f James*

t h e s e w o rk e r a th o ro u g h ly I n v e s ti g a te d th e I n s p i t e o f t h e f i n d in g s o f &ebean and J£ar-

WteaWt D tle p ln e m k Y l l l e i n s i s t e d t h a t t h e p r o d u c tio n o f e th y le n e h r o m o a h lo r ile was due t o t h e in te r m e d ia te fo rm a tio n o f brom ine c h lo r id e *

f h e j b e lie v e d t h a t brom ine c h lo r id e

was a compound w hich d i s s o c i a t e d t o su ch an e x te n t t h a t i t escap e d d e t e c t i o n by p h y s io a l means#

fh e a e I n v e s t i g a t o r s

a l s o added t h a t t h e m in u te u n d le s c a la te d p o r t i o n r e a c te d much more r a p i d l y w ith e th y le n e th a n e i t h e r brom ine o r c h lo r in e # I n 1928* a s p r e v io u s ly m e n tio n e d , F r a n c is (5) r e p o r te d t h e a d d i t i o n o f brom ine c h l o r i d e t o sodium male&te and e t h y l e n e | f? e rr y and H lo h e lb e r g e r ( i ) added i t to fu m a ris s o ld and m e le lo a c id *

Whit® and B o b ertso n (5.3)

1?

S tu d ie d t h e M n e tle © of t h e a d d i t i o n o f bromine c h l o r id e t o els*etius:fta&ie a c id b u t f a i l e d t o d i s c l o s e th e n a tu r e o f t h e p ro d u ct?

fextap* th e b e s t p ro o f o f the e x i s te n c e o f brom ine e h l e r i i e ? based m fr o d a c t a n a ly s is * mm offered by f a y lo r and

Wmmw (4 1 ) * When tr e a te d w ith c h lo r in e or bromime*

a l i p h a t i c d la a e compounds are quantitatively con verted to

the aihalegen derivatives 1

B

R1

S'

f h e s e i n v e s t i g a t o r s re a s o n e d t h a t i f t h e d ia s o compound w ere t r e a t e d w ith equintoleeul&r am ounts o f brom ine and c h l o r i n e t h e p ro d u c t sh o u ld c o n s i s t o f a m ix tu re o f th e brom eehlor© ** dichlere**.# and dihromo^compounds*

I f no com*

p i1eating f a c to r© w ere p r e s e n t* th e p r o p o r tio n s o f th e th r e e product© form ed sh o u ld he a measure

of th e p r o p o r tio n s

o f c h lo rin e * , brom ine and brom ine c h l o r id e in th e o r i g i n a l m ixture.#

A c c o rd in g ly * th e y t r e a t e d a ca rb o n t e t r a c h l o r i d e

s o l u t i o n o f d ia s o d e s e x fb a n s o in * e q u lm o le c u la r m ix tu re o f "C hlorine and bromine*

w ith an fh e p ro d u c t

c o n ta in e d 80 mol# # o f b romoc h lo r ode coxybe na o i n and 10 mol*

$ each o f d lo h lo r o * and dibrom o* desoxybensoin#

’P hase

w o rk e rs co n c lu d ed t h a t th e same p r o p o r tio n s e x is te d in th e

fttttlite itiK *

01^

B rC i ( §0$) *

In 1:90ft' con siderab le doubt o f th e ex isten ce o f i r o s t n i ' c h l o r i t e r e s u l t e d from th e i m m H g m t l o m of

bmmm m i £iur«t#M *

B a r tb e lo t

{z$\ hat already q u estio n ed

th # formation o f t h i s compound because o f i t s low heat of reaction?

ihet* he mixed bromine and ch lo rin e at a temper** A

a t up# o f 0 * I*fee&i» {M ) noted t h a t n o th in g i Mica t o t the s t a r t o r f i n i s h o f a r e a c t i o n ; t h a t no one hat a c t u a l l y shown i f the compound mm® form ed or w h e th e r i t was m erely a mljctupes o f bro m in e a n t c h lo r in e * o n e d is s o lv e d in th e o th e r #

if»Ma& a n a i y e t i b ro m ia e * c fe le rln e m ix tu r e s a t

tem per& lm reg r a n g in g t o *80° and found t h a t th e c h l o r in e c o n te n t v a r ie d w ith th e tem p era tu res o f c r y s t a llis a t io n * Be a l s o d e te rm in e d t h e m e ltin g p o in t c u rv e o f bromine** C h lo rin e m ix tu r e s from *$#$■ * t h e m e ltin g p o i n t o f brom ine* o to *102#$ * th e m e ltin g p o i n t o f c h lo r in e * fM s curve mm s l i g h t l y co n cav e a n t t h e same a s w ould h e e x p e c te d f o r m ix tu r e s o f tw o M babane*® w hich form c r y s t a l l i n e m ix tu re s w ith o u t a d e f i n i t e c o m p o sitio n *

f h i s e v id e n c e t le b e a u

c o n c lu d e d ? showed t h a t t h e compound brom ine c h l o r id e d id n o t a g l e t ! th a t it® co m p o sitio n depended on th e elrcom-* o s t a n c e s o f i t s f o r m a tio n ; and, t h a t a t 0 I t was a s o lu t io n o f brom ine i n c h l o r i n e o r v ic e v e rsa * S i m i l a r l y , h& psten ( zf\ s t u d i e d - t h e b o ili n g p o in t c u r v e o f h r o m la e ^ c h lo r ln e m ixture® and re a c h e d th e same

19 ft$ fteln * iM ft e g a n k M i i t Oft t h e e t h e r h a n d # Andrews aM a& riton. {88} M ftlttM t h a t t f t M l t y ttftftftWftftfttttft o f b r o m in e - c h lo rin e mix­ t u r e s I n d i c a t e ! t h a t brom ine c h l o r i d e t i t e x is t*

lu x (39}

pfttojeeteft a m ix tu re p ro d u ced from ab o u t ®q.ml part© o f c h l o r i n e a m b ro m in e %o. sle w d f a t t l l a t i e a aM removed gome i i a t . l l l a t o gmmplte*

.f a r t o f th e sam ple was used f o r d e te rm i­

n a t i o n o f a w a fe r p r e s s u r e c u rv e s th e r e s t wee analysed f o r bromine and c h lo r in e eontem t*

l e x found th a t one sample*

m e ltin g s h a r p ly a t *34°# p ro d u ced a vapor p r e s s u r e cu rv e w hich oouM he a t t r i b u t e d o n ly t o a compound n e ith e r

W m l m m % c h lo r in e *

H alogen a n a l y s i s o f t h i s sam ple

ehcwM. one c h l o r i n e atom p r e s e n t f o r e v e ry brom ine .atom*, A loe* $&x n o te d t h a t t h i s compound was more v o l a t i l e th a n brem l m *

Moreover.# Andrew* and C a r lto n ($ s ) o b se rv e d a

c o n t r a c t i o n i n volum e when l i q u i d c h l o r i n e . and brom ine w ere m ix#!#

t h i s c o n t r a c t i o n amounted to a b o u t *0$ o f th e t o t a l

volum e.

Cray and S ty le (3 4 ) r e p o r te d t h e ab sen ce o f a do*

c r e a s e i n p r e s s u r e when m ix in g g a se o u s bromine and c h lo r in e , t h e e v id e n c e o f t h e s e w o rk e rs s tr o n g ly in d ic a t e d t h a t a c t u a l c h e m ic a l c o m b in a tio n betw een brom ine a n t c h lo r in e to o k p la c e a t l e a s t to a lim ite d e x t e n t , and th e p ro b a b le

formula was BrQl. More e v id e n c e was o f f e r e d by f o r b e s and Foosa (SO)

ao who s t a M e t th e r e a c t i o n b etw een brom ine aM c h l o r id e io n in t h e p re se n t-# o f h y d r o c h lo r ic a c id *

A n a ly se s o f th e o x i­

d a t io n p o t e n t i a l s o f a c h l o r in e - h y d r o c h l o r ic a o ld s o l u t i o n t o w hich was a id e d m m & m i m p o r t i o n s o f s o l i d brom ide io n l e t t o r e s u l t s w hich w ere a n a lg o u s to th o s e o b ta in e d from a s i m i l a r I n v e s t i g a t i o n o f a c i d i c l o d ln e - o h i o r i n e (U®** io d in e m o n o o h lo rid e ) s o lu tio n s * .

tk®$ found th e norm al p o t e n t i a l

o f b ro m in e c h l o r i d e mad c a l c u l a t e d th e e q u ilib r iu m c o n s ta n t* S*pSPgJ [ e i ^ / [ B r C ^ 8 * 8 * 8 1 0 * 8 * 10*4 I n e l th e y an , o r H * h y d r o c h l o r i c a c lf *

f j^ a le e c h e m ie & l p ro o f o f th e fo rm a tio n o f th e eenpm w d brom ine c h l o r i d e in c a rb o n t e t r a c h l o r i d e was f u r n ic h e d by B a r r e t t and S te in and by 9 'illa m

m i M orten*

it

was fou n d t h a t th e a b s o r p tio n o f l i g h t by th e m ix tu re s * in th e v i s i b l e region#, was m a rx e d lf l e s s th a n t h a t o f th e brom ine c o n te n t a lo n e *

Assuming th e a b s o r p tio n c o e f f i c i e n t

o f t h e in te rh & lo g s n compound t o be n e g l i g i b l e ( e x a c t wave le n g th n o t s t a t e d ) # B a r r e t t and s t e i n (3 1 ) c a lc u la te d e q u ilib r iu m c o n s t a n t s f o r th e d i s s o c i a t i o n o f brom ine c h lo r id e # o b ta in in g a mean v a lu e o f Q*S3«

h a te r# f e s p e r and

BoXlelwoa (BB) r e c a l c u l a t e d t h i s d ata# ( maXlng an allo w an ce f o r th e a b s o r p tio n o f brom ine c h l o r i d e ) # and found a v a lu e n o t g r e a t e r th a n 0*18*

the r e s u l t s o f V ilia m and M orton (be)

w ere q u a l i t a t i v e # b u t th e y e s tim a te d t h a t th e arcm ine

21 s h l o r i d t m i Im n th a n SQjS dies© aiatM *. @yay and S t y l f (34) measured th e a b so rp tio n o f

$l i m i t M x tu r w o f e h lo r in e ana bromine and found a s im ila r d e c r e a se o f th e bromine a b so r p tio n upon th e a d d itio n ©f c h lo r in e *

Assuming t h a t a t 0 « 5 7 9 / t i h * a b so rp tio n o f

brom ine e h lo r ld e was n e g lig ib le * d ata from two experim ents gave & .the v a lu e s 0*132 and 0*125*

Again* Temper and B el­

iefs© © {33} claim ed t h a t i f bromine c h lo r id e did absorb s l i g h t l y a t 0 .5 7 9 /v * &£&* i f th e ra ti©

10 ° * 0 1 *

th e raja® * o f I o b ta in ed from th e gray and s t y l e m ixtures were 0*121 and 0*114*

In a s im ila r manner, th ey assumed

O ther v a lu e s f o r th e r a t i o s o f th e a b so rp tio n c o e f f i c i e n t s and found t h a t a t eCorC! / o f d a ta *

*0*0124, X*Q*X!1 fo r both set® Br^

y©s% (3 5 ) h a s made m easurem ents o f g aseo u s e q u i­ lib r iu m a t te m p e r a tu r e s b etw een 0 ° and &$O0 u s in g a s ­ su m p tio n s s i m i l a r t o th o s e o f g ray and S ty le *

Be gave -

v a lu e s f o r th e e q u ilib r iu m c o n s ta n t a t room te m p e ra tu re r a n g in g from 0*10 t o 0*22* Y ost (.35) h a s o b ta in e d a v a lu e o f 0*12 t o 0*14 f o r th e e q u ilib r iu m c o n s ta n t a t room te m p e ra tu re and e s t i ­ m ated t h e h e a t o f r e a c t i o n a t 300 o a ls * B e in g t h e g re e n l i n e s o f th e h eliu m d is c h a r g e , w ith © e n te r o f g r a v i t y 0 * 5 0 2 ^ a s tr a n s m itte d by th e f i l t e r

ZZ

u e e i* V espey and Beliefs© ** (33) m easured b o th th e d i s s o c i ­ a t i o n c o n s ta n t a n i e x t i n c t i o n c o e f f i c i e n t o f g aseo u s bromine c h l o r i d e by s u i t a b l e v a r i a t i o n o f th e p r e s s u r e used*

it

t h i s wave le n g th * th e r a t i o *fcq / < , was n e a rly 0*1* so t h a t ^ 3fcj m $

®[email protected] urei w ith r e a s o n a b le accu racy *

At

80° t h e v a l u e s £* p r ^ | p l J / @ r a i | SssQ*lG¥to,Q08 aoao(«lQ g ■!g/XtQ*!MH* 0 * 0 0 0 w ere found* S o ta ts a (37) m easured t h e e q u ilib r iu m c o n s ta n t a t S00°G» and 000% * f i n d i n g - v a l u e s o f Q»13&$ and 0*14 r e ­ s p e c tiv e ly * B eeson and l o s t (38) o b ta in e d th e v a lu e 0*148± 0*011 a t 4& i% *

They a l s o r e p o r te d th e therm odynam ic

v a 'lu e s i A ly - 4 6 S e o ls g ^1Ft «-465-8*8ST * V esp e r and l o l l s f s o n (33) a l s o o b serv ed t h a t s ix t y h o u rs w ere r e q u ir e d t o a c h ie v e e q u ilib r iu m i n th e d a rk ;

two

m in u te s by i l l u m i n a t i o n w ith u l t r a v i o l e t l i g h t ( Q*388,a ) ; a b o u t t h i r t y m in u te s by f r e s h l y c le a n in g th e w a lls o f th e r e a c t i o n v e s s e l w ith o u t illu m in a tio n *

T his* o f co u rse* i n ­

d ic a te d a f r e e r a d i c a l mechanism* T hese o b s e r v a tio n s w ere co n firm ed by B rau e r and V ic t o r (4 0 ) who s tu d ie d t h e k i n e t i c s o f t h e r e a c tio n 0 [email protected] + Q l9 *==*£BrOl i n th e g a s phase* They m easured th e e f f e c t e Br* A Br* + 0 1& . — * B r -c i + o i* Cl * + Brg — *B r-01 +- Br *

4*6*0 Koal*

4)

e i* + B r o i—* e i g + B r *

4*5*7 Kcal*

5)

Br* + B r 0 1 —»Brg -|- 01*

-6*0

6)

Br* ■+ B»+w — ►Brt>

4*45*2 kc&I*

1) £)

- 5 .7

Kcal.

Koal*

f o r th e r e a c tio n i n th e darks l)

B rtt+W — >2 Br*

- 4 5 .2 Kcal.

H © actions 2 -5 a s above

6)

Br« -+Br« + W ------

They d e s ig n a te d S te p 2 a s r a t e d e te r m in in g .

4*45.2 Kcal*

B o rin g t h e & m t m o f an i n v e s t i g a t i o n ©f a pos* a iB le m echanism f o r s u b s t i t n i i o n r e a c tio n s * Wohl t r e a t e d a e e rie ® o f eenpoun&a w ith M*Br©moae e t a mi d e (4& ).

Be r**

f o r t e l t h a t B ro m in a tio n o f sttB & tan eeseo at& in in g a c t i v e h y d ro ­ gen p ro c e e d e d sm oothly*

lorn Brg+Ae$Jt*

irg th i/ a r 8 +;ej»r-8C

»g Br* *

X'Br»»

n

( OgHg) gCBrCHBrGgHg tl OBGlg+HBr OHClg+bv

51

33 M e a tm e io n i s a p a r t i c i p a n t i n a d d i tio n r e a c t i o n s t o t h e ole-* f i n l e S oall®

li-brem o& oetam i &© h a s been re p o r te d (1 5 ,4 8 ,

49*151} t o be a s o u rc e o f brom ine*

B u ck les (|$1) h as demon­

s t r a t e d t h a t i n t h e p re s e n c e o f acid,,, t h i s brom ine a c t s a s i f i t w ere p o s i t i v e and t h a t th e r e a c t i o n proceeded v ia an ie& ib# &*$* btfom oalw io n 113}* in te rm e d ia te *

I f h ^ d ro -

brom ic a © if i s u sed * p o s i t i v e brom ine c o u ld be formed from e i t h e r t h e ee& jog& te a c id o f N*brcmo&cetaml&6. (jUUtfl) o r m o le c u la r brom ine (§15*

f!me» th e o v e r a l l a d d itio n o f m ole­

c u l a r brom ine t o th e e t h y ie n l o d o u b le bond co u ld p ro ceed b f C i th e r o f b o th o f th e two schem es (a*b) o u tli n e d below* AeNESr + HBr ,— - AaKIgBj^+Br XXXVI

■gpt A oS I„3rf + 2o*cc ------» X ^ C C -h AcOT S'

to * •>oz ^ ck+ i r *

— - 4 ^C B r-t^r

AoHBgBrV Br" — —) Brg + AcNSg rxynrT

*L

Bsf„ +->0»C
3 r -a -t> r

S e v e r a l w o rk ers have n o te d t h a t th e a d d itio n o f m o s s 's c h l o r i d e io n t o an o le fin * b ro m in e s o lu t io n r e s u lt e d

34

in th e a d d itio n of^bromine chloride* to th e double bond (84, ft9*ftv* v41)«

The form ation of th e o le f in bromoohloride was

s h e w to proceed by way o f a broaoaium ion in term ed iate ( 13)* th e r e f o r e , I t seemed pro b ab le th a t th e a d d itio n of c h lo rid e l e u to a m ix tu re o f l*bre® & oet-aaide and an o le f in would

mlm r e s u l t in th e a d d itio n of''brom ine c h lo r id e 'to th e d o u b le bond# i n o r d e r t o t e a t th e - v a lid ity o f t h i s a ssu m p tio n , e th y le n e b r o m o e h lc rid e , a known compound (£4* 8 9 ), was p re * p a re d i n %%$ y i e l d by th e sim u lta n e o u s a d d i tio n o f N-broraoa e e ta m id e a n t e th y le n e t o a m ix tu re o f w a te r and c o n c e n tra te d h y d r o c h lo r ic ac id * O th e r a tte m p ts t o p r e p a r e e th y le n e b ro m o eh lo rid e r e s u l t e d i n t h e fo rm a tio n o f e th y le n e d lb ro m id e a s th e m ain r e a c t i o n p ro d u c t#

T hese a tte m p ts in c lu d e d th e u se o f

c h lo ro fo rm , -e th e r -and a c e t i c a c id a s s o lv e n ts and v a ry in g th e r e a c t i o n te m p e ra tu re # The a d d i t i o n of'"brom ine c h lo rid e * to th e e th y le n ie d o u b le bond would be e x p e c te d t o ta k e p la c e i n such a manner t h a t th e c h l o r in e would be lin k e d t o t h e carb o n atom c a r r y in g t h e l e a s t number o f hydrogen ato m s, 1 »e«, "Harkownik o f f a d d itio n * #

T h u s, 1 -b ro m o ^ -o h lo ro p ro p a n e would be th e

a n t i c i p a t e d p r o d u c t r e s u l t i n g from t h e a d d itio n o f'b ro m in e C h l o r i t e 1t o p ro p o n e $ and & lp h a* ah lo ro ~ b eta~ b ro m o eth y l

86 benaenw ( X U T I I) fro ® e t y r e n o .

f h e l a t t e r oompouad was p re *

p & te f ky t r e a t i n g a w a ta r - a o n e e n tr a te S h y d ro o b lo rio a o id AeSHBr+HC1

.■

A «SIgte * + 0 l»

* AcHH Br*+ 01“ * —

B & l”+ 06H5 -CH»CHg

3#Cl*+AoKHg > C6Hg-0H ^C H 2 - C l *

By*

ox* ■— > oeEfi*o»oi*aa *Br XXXflX a& x tn re w ith I-ferom o& cetM ld© ami s ty re n e *

I t was neees*

M Xf t o m a in ta in t h e te m p e r a tu r e o f th e r e a c t i o n m ix tu re a t > 8 t© § «.

When t h e r e a c t i o n was allo w ed t o p-rooeed a t a

te m p e r a tu r e o f 10°* t h e p ro d u c t waa alm o st e n t i r e l y s t y r e n t diferom ide*

Bibrom i& e fo rm a tio n was a l s o r e s t r i c t e d fey

a d d in g t h e s^ h ro m e a e e ta m id e p o r tlo n g w is e * w a i t i n i f o r th e l o c a l fe ro & in e -lik e c o l o r t o d is a p p e a r B efo re t h e ©ext au­ d i t ion#

t h e y i e l d s o f s ty r e n e h ro m o e h lo rid e war le d from

36 t© 44$*

S ty ra n # aiferom ide was a l s o p r e s e n t m

p ro d u c t l a 1 t o T% y i e l d s #

a fey-*

S e p a r a tio n was acco m p lish ed fey

f r a c t i o n a l d i s t i l l a t i o n th ro u g h a T ig re u x column# alpha^Ghlor©^feeta-fero.m [email protected] thyl b en sen e, a compound n o t p r e v io u s ly r e p o r te d i n th e l i t e r a t u r e # , l a a c o l o r l e s s s t a b l e l i q u i d w ith a p e r f u m e - lik e o d o r re se m b lin g th e a lp h a o r b e ta h a lo a ty r e n a a #

I t s b o i l i n g p o in t i s i l l - l l d

0

36 ( a t 7 mb,} OS 98*38° ( a t 8 .8 a w .)} a 2% 1*8770) d s0 4 1 .4 9 8 ( l 3r®n.®©©|«^j|

t h e c& tM n-hy « rogen aM t o t a l h a lo g en

Im&l*

t i e d Step&now). a n a ly s e s a p e e i c l o s e l y w ith to© valm.es c a l ­ c u l a te d m

th e b a s is o f

*

In e r t e r t o sh e # t h a t t h e c h l o r i n e atom w as a t # ts e h e d t o t h e e&rbem atom w hich i s a lp h a t o t h e M a s an a rin g * a sam ple o f atyaf©n# brom oohloriA # w as t r e a t e d w ith a l ­ c o h o l lo sodium hydro$l&.« ( 5 4 )•

H ydrohrem io a c id was t h u s

rem oved from t h e m e ie e m lt t o form a l p h a - c h l o r e s t y r e n e (H X fl

1 1 ) in

f¥*$$

y ie ld *

fh e a X p h a-oh lorostyren e was

I d e n t i f i e d by co m p arin g I t s p h y s i c a l p r o p e r t i e s w ith th e v a lu e s r e p o r te d I n t h e l i t e r a t u r e ( $ 4 #&&*&$) ana by I t s con­ v e r s i o n t o a e e te p h e n o n e by tr e a tm e n t w ith s u l f u r i c a c id a t SO0 #

I t w as a l s o I n t e r e s t i n g t o n o te t h a t a lp h a ^ O h lo ro -

s ty r e n e * w ith t h e c h l o r i n e atom I n b o th th e a l l y l i e and o jf -o h o i» o ijte -tnmw D O 4

XXJTVxi» TT

-» CgI&C01»eBg +HBr

XXMUl

0 .»,*CG1*CH(. +H SO 6 8 % % • v i n y l p o s itI o n a * gav e a p o s i t i v e t e s t w ith h o t a l c o h o l i c s ilv e r n itra te * I t a l s o seemed p r o h a h le t h a t a n o th e r d e r i v a t i v e o f a l p h a - e h lo r o s ty r e n e so o ld be s y n th e s is e d W

a p p lic a tio n

o f a m ethod need f o r t h e p r e p a r a t i o n o f t h e a n l l i d e d e r iv e # b it® o f h a lo g e n c o n t a in i n g hydrocarbon® {§?)*

A c c o rd in g t o

t h i s method^, t h e a n ill& e o f a tro p i© a c id iXXXIX) s h o u ld h e form ed by t r e a t i n g t h e d r i g n a r i r e a g e n t o f a lp fc a -e h lo r© s t y r e n e w ith p h e n y l le o e y a a a te *

how ever* a l l attem p t® t o

p r e p a r e t h e d p ig u a rd r e a g e n t f a i l e d *

f h e a e e f f o r t®

0 6l g-001»QSg +Mg --------->GgH§-€MgCl»GI£ X X lT lil o ^ - a w c is o B j.o ^ M M

-mfy**

_____________ f l w a _ __ « OBg&of c ftH5)*d»K*c6Hg h-m i -1 p * c % 2 a ( c 6H g ) - a ^ H a eH5

in e lu d e d © ntrainm ent*. a d ry n itr o g e n atm o sp h ere and th e M pper^atagneaiam a l l o y c a t a l y s t recommended by Oilman {58) ♦ f h e p r e p a r a t i o n o f a lp h a - o h lo r o - h e ta - h r o m o e th y l benaen© was a l s o a e o e n p lla h e d by a n o th e r method*

P fe iffe r

and l i s t e r t ( 8 @ ) r e p o r te d t h a t e t i l h e n e bro& oohlorl& e c o u ld be p r e p a r e d by t r e a t i n g m e s o - s tilb e n e d lh r o e ld e w ith a n ­ h y d ro u s s t a n n i c c h lo r id e *

fv e s tm e n t o f a d ry b enaene

s o l u t i o n o f s ty r e n e dibrom id© w ith an h y d ro u s s ta n n ic c h l o r i d e p ro d u ced an SO*4$ y i e l d o f s ty r e n e orom oohlorid® (M JO T in U

t h i s s u b s t i t u t i o n r e a c t i o n p ro b a b ly to o k p la c e

sa tej way ©f. a earh o n lu m ion- in te r m e d ia te (X I) i C ^ G llr^ G H ^ B r + Se C14

> C6B ^G H ~ 0!s Br -I- BnGX^lr* Hi

C$HBCH-OHgB r + flaOl^Bv"

»Q

+ BnCX^Br «6m6n#»VJLayX

fk la prod act wan found t© be identical with the styrene btoiaochUride praeieualy prepared#

$hw physical constant©

were Is wsewMwat agreement ant the aw© derivatives* alpha*w!&ew©eiyre»w and acetopheson# «* war© ©stained by tha ywewtiwnw dwawrihed above* I t a p p e a re d wya&lfelw t h a t th e Iso m er t alp h a^ b ro m o beta*© hIor© ethyX fewnawnw ( 1 H I ) # would h e p ro c u re d by t r e a t i n g © tyres© w ith B*ohl©[email protected]©etamide and fcy d ro b ro aie a©i&*

I f t h i s a a a u a y tlo n w ere c o r r e c t* th a r e a c t i o n s h o u ld

p ro c e e d by way o f a o h lo ro n te ® io n I n te r m e d ia te (XLX), a c ­ c o r d in g t o w ith e r o f t h e aehemea f e t 4) o u t l i n e d below* e)

n

* o cftso i + tsi>

r = = ? m B^QomzQf n- B r"

c i-G O ffH ^ o iV B r* * = * oi* B r" + gh^ gonh ® * x ox* * e ^ « c H * o » a +* o r B r" — > o6h 6- ot ^ oh8 + B r" XH g 6h 5- cb 2* ch2

+ a r " — » o .H s * ca» r-o H gcx

axxi

89

3}

e i z *00BH3Gl++ GgSg-fiSacig

Cl+ i GgHg-CH^Hg+CEgCQNHg

+

ja i

C6H&-G B ^0B 2 + B r" ------> CaHg-C © r-O E ? Cl

jy .ii t h e s im u lta n e o u s ad a I t 1 00 o f J$ ~ ah lo ro aa eta® iae

m & at;$ m m t o a w a t 0r - c o n c e n t r a t e& hyfirobrom le a c id mix** t a r t a t a te m p e r a tu r e o f 0° gave s ty r e 00 d ib ro m id e a s th e o n ly p r o d u c t*

The same p ro d u c t was o b ta in e d when th e re *

a c t i o n was e a r n e d o a t a t a te m p e r a tu r e o f $©°*

The a c i d

c o n c e n t r a t i o n was h a r l o t and t h i s a l s o f a i l e d t o p ro d u ce a ty r e n * b ro m e c h lo rid e #

The

h i 0ro a e e ta m i de was f i r s t

t i a e e l r e d i n w a te r and t h i s m ix tu re added* a lo n g w ith s ty r e n e # t o th e aq u eo u s a c id 5 b u t o n ly th e aibrcm i& e was o b ta in e d #

The same p r o d u c t wasr p ro d u ced by t r e a t i n g a

c h lo ro fo rm s o l u t i o n o f s ty r e n e w ith U * c h lo ro a c e ta ® id e and and g a s e o u s h y d ro b rc m lc ac id *

However# when c o n c e n tr a te d

hydrobrcM&lo a c id was added w r y slo w ly to a m ix tu re o f w ater# N * e h lo ro a a e ta m id e and s ty re n e # a s m a ll amount o f a s u b s ta n c e c o n t a in i n g brom ine and c h l o r i n e was i s o l a te d *

A m ix tu re o f e th e r# N -o h lo ro ae& tam id e and s ty r e n e

0

was c o o le d t o 0 *

C o n c e n tra te d Mydro'bromie a c id was

slo w ly in tr o d u c e d t o th e r e a c t i o n m ix tu re a t such a r a t e t h a t th e te m p e r a tu r e rem ained unchanged#

In t h i s manner*

a $&$ y i e l d (b a se d on Jfc-chloroaeeiam ide and s ty r e n e

40 fcro m o o h lo riae) o f a c o l o r l e s s l i q u i d , b*p* 1 1 1 -1 1 5 ° (7 mm.*} w as found t o c o n t a i n brom ine ana c h lo r in e * t a t i t s r e f r a c t i v e In d e x {s$% 1*$$60) was lo w e r th a n th e a n t i c i p a t e d v a lu e ln ^ % l #g7TO)*

M o reo v e rf t h e v a lu e s o f t h e t o t a l h a lo g e n

f o u n t an4 th e v alu e® c a l c u l a t e d f o r s ty r e n e b rom oehlori& e d id n o t a g re e *

f h e fo rm e r m easurem ent was c o n s i s t e n t l y 7jl

lo w e r th a n t h e l a t t e r *

fh u s * I t a p p e a re d t h a t t h i s l i q u i d

w as a M ixture- o f s ty r e n e b ro m o o h lo rid e and a n o th e r p o s s i b l e r e a c t i o n p r o d u c t# h e r e a f t e r r e f e r r e d t o a s WX%

fh e f o l­

lo w in g p r o p e r t i e s w ere assum ed t o he p o s s e s s e d >hy f*Z*| a b o i l i n g p o i n t w ith in o r v ery c lo s e t o th e ra n g e 1 1 1 -1 1 5 ° (7 am) i a r e f r a c t i v e in d e x l e s s th a n t h a t o f s ty r e n e brom oc h l o r i d e s and a c a l c u l a t e d v a lu e f o r t o t a l h a lo g e n w hich w ould he l e s s th a n t h e - v a lu e s found*

f h e m ost p r o b a b le r e ­

a c t i o n p r o d u c ts i n a i d i t i o n to s t y r e n e brom ochiorl& e and s t y r e n e d ih ro m id e w ere th e e h lo r o - and fcromeJiydrias*

S ty ­

re n e d i c h l o r i d e was n o t c o n s id e re d s in c e no f r a c t i o n was o b ta in e d a t i t s b o i l i n g p o in t (1 1 4 -1 1 5 ° /1 5 mm*}*

A com­

p a r i s o n o f t h e b o i l i n g p o i n t s 'and r e f r a c t i v e i n d i c e s o f t h e s e p o s s i b i l i t i e s w ith th e mixed p ro d u c t i s sh o w n -in f a b l e XXI*

fh i® t a b l e r e v e a l s t h a t a m ix tu re o f s ty r e n e

b ro m o c h lo rid e and s ty r e n e o h lo r o h y d rin c o u ld g iv e t h e r e ­ f r a c t i v e in d e x and b o i l i n g p o in t o b serv ed f o r t h e m ixed p ro d u c t*

41

Qeapoanft

Heo B

B*F*

t r e a s u r e (mm*)

S ty re n e brom oohlorid©

1 1 0 -1 1 4 °

?

1*5770

S ty r e n e h ro m o © h lo rl4 e+ rtZ ,1

1 1 1 -1 1 3 °

?

1*5560

S ty re n e o h io ro & y d rin (6 ? )

1 1 0 -1 1 1 °

6

1 .5 4 0 0

S ty r e n e bromehy4F in (6 8 !

1 09-110°

3

1*6800

S ty re n e 41bromi r» 0 H6+Sa014 ------- > CaI g-€f*-aS B r-aeHg^sn014Br“

xm 0 I ft* J H * fln r* 0 4» fi+SttCl4B r" ----- »C6H5CH01-0HBr-06H ^ n C lgBr

jYTTV OmmuV d mixed m e ltin g p o i n t o f th e s e two sam p les gave no d e p re s s io n # I n a s i m i l a r manner# a m ix tu re o f t h e h ig h e r and p r e v io u s ly uxireported lo w e r m e ltin g iso m e rs o f s tilb e n © b ro m o o h lo rid e was o b ta in e d from o is ^ s tilb e n e #

3?he iso m e rs

w ere s e p a r a te d by f r a c t i o n a l c r y s t a l l i s a t i o n from 95$ e t h y l a lc o h o l*

A 4.6#©$ y i e l d o f o i s - s t l l b e n e b ro m o ch lo rid e* m*p*

99-100°* and 13*5$ o f t r a n e - e t i l b e n e brom oohlori& e was o b ta in e d #

46 fre m tm e u t o f e i 8 * s t i l b e n « w ith brom ine r e s u l t s In t h e f o r m a tio n o f a i* e iilb e n © ilb ro m ld e in 46*8$ y i e l d f i n s a ©mall amount (1 3 # $ 4 $ o f th e m es© -*stiloene d ib rcm id e*

fh0 ©mall amount o f t h e h ig h e r m e ltin g iso m er was due e i t h e r t o t h e c o n v e rs io n o f p a r t o f t h e o i8 * » s tilb e a e to tr a n s * © tilb e n e p r i o r t o th e brom ine a d d i t i o n o r t o a f r e e r a d i c a l m echanism o f brom ine a d d itio n *

fh u s* I t i s n o t - s u r p r is in g

t h a t th e h ig h e r and lo w e r m e ltin g isomer© o f a tilb e & e b rem e eh lo rl& e w ere a l s o o b ta in e d in p r a c t i c a l l y th e same r e l a t i v e y ie ld s *

f h e lo w e r m e ltin g iso m er o f s t i l b e n e

b ro m o o h lo rid e h a s n o t b e e n ,p r e v io u s ly r e p o r te d *

m

A lth o u g h

fo rm a l s t r u c t u r e p r o o f i s o f f e r e d , i t s fo rm a tio n i s a n a l*

ag o u s to t h a t o f & l* s tilb e n e dlbreml&e*

S in ce th e ad*

A it to n o f bro m id e io n t o th e o ia* & tllb en © hromoniom io n i n te r m e d ia te p ro d u c e s th e lo w e r m e ltin g ( i«e« d l* ) s t i l b e n e d ih ro m id e , i t i s r e a s o n a b le t o assum e t h a t a d d i tio n o f c h l o r i d e io n t o t h e same in te r m e d ia te would p ro d u ce th e c o r r e s p o n d in g iso m e r o f s t 11bene b ro m o a h lo rid e ( th r e e ) * ay rj a H*0*Br 1 * 0*01

C1*C*B G*H

m#p« 33&~££3° e ry th r o~ s t i 1 ben© b ro m e e h lo rld e

aup* 99*100° t h r e o * s t i l b e n e b ro m o o h lo rid e

The a d d itio n o f bromine t o cinnam ic a c id can a ls o be p ic tu r e d aa p ro ceed in g bp wap o f a bromcnium Ion in t e r * m ed iate

(0 7 1 ), The a d d itio n o f hppobromoue a cid t o cinnam ic

C^Bg-CHSCB-COgH + f lr g ----- > CgBg-CB^CH-OOgH +Br*

an

Br* SgBg*CH“ CH*OOgB + Br“ -----» OgBg -CHar-CHBr-COgH a c id p rod uces alpha-brom o-beta-hydroxp-hydrooinnam ic a c id ( -SBVI I ) .

T h is in d ic a t e s t h a t the b eta carbon atom o f th e

bromoniam io n In term ed ia te (JttV) i s more p o s i t i v e than th e alp h a carbon*

T h er efo re , th e a d d itio n of"bromine c h lo r id e

G^H JgJ $ @~CH^H~O0*B 4 + 0I~ ----- » QJ^-CBQH*0KBrM30 § § ttV I

XLTII

t© cinnam ic a©id should produce alpha«toroi8o*beta*ahlor0"» hydrooinnam io acid * T h is a d d i t i o n was acco m p lish ed by t r e a t i n g a M * m eth y l e e l l o s o l v e s o l u t i o n -of cinnam ic a c id ana hydro* c h l o r i c a c id w ith $*[email protected]*

The d e s ir e d p r o d u e t,

aX p h a-h ro m o ^ h eta'-eh lo ro ^ h y d ro o in n am ie a c i d , was o b ta in e d in $£«7$ y i e l d , m#p« 180*181°* The c h l o r i n e atom was shown t o be lin k e d t o th e b e t a c a rb o n by t r e a t i n g cinnam ic a c id b ro m o e h lo rid e w ith a l c o h o l i c sodium h y d ro x id e* cin n a m ic a c id was p ro cu red *

A 54*3$ y i e l d o f alpha*brom o*

48

f i l l s defcydrohalegen& tlon r e a c tio n wa® somewhat an-* u su a l in th a t hydrogen c h lo r id e gen bromide^

wm

removed in s te a d o f hydro*

On th e o th e r hand, s in c e d eh y d ro h a lo g en a tio a

r e a c t io n s in v o lv in g s im ila r a c id

a c r y lic * e r o to n ic *

cinnam ic) di'broroldea and d io h lo r id e s proceed e a s i l y t o y i e l d th e r e s p e c t iv e a lp h a - h a le - d e r lv a iiv e s * th e form ation o f t h e same d e r iv a t iv e in th e above r e a c tio n was not an* u su al*

M oreover, th e removal o f hydrogen bromide from a lp h a -

b rom o-h eta-oh loro-h ydroein n am ie

w ould, o f course* in v o lv e

th e removal o f bromine from th e alpha carbon atom*

I t har

been rep orted (6$) th a t a d eh yd roh alogen atiea r e a c tio n o f t h i s ty p e ( i.»e,» t i g l i c a cid dibrom lde) proseeded w ith d i f ­ f i c u l t y and req u ired more d r a s t ic c o n d itio n s than w ere used in th e above re a ctio n *

49

BfefM moles of fresh ly fused aeetaralde and 3 moles of bromine were put In to a 1 1* * thr©e*neeked round bottom fla s k which was equipped with a mechanical s tir r e r *

The © tirre r was s ta rte d and the aeetamide was

eompletely dissolved in th e bromine#

(F ailu re to dissolve

the aeetamide completely p rio r to the addition of pot&s* alum hydroxide re su lte d in a very low y ie ld of'H^bromo* aceiamid©)*

fh© re s u ltin g solution was cooled to *6®#

• f h re e m oles o f p o ta ss iu m h y d ro x id e was d is s o lv e d i n enough w a te r

t o make a s o l u t i o n ©f 300 ml#

t i e n was c o o le d

t o 0°#

5 h is

so lu *

When t h e a c e ta m id e had d is s o lv e d * th e b a s ic s o l u t i o n was added a t such a r a t e t h a t th e te m p e ra tu re o f th e r e a c t i o n m ix tu re rem ained betw een **8P and 0''#

A f te r

th e 300 ml# p o ta s s iu m h y d ro x id e s o l u t i o n h a s been added* t h e r e a c t i o n m ix tu re sh o u ld be a l i g h t y e llo w c o lo r# Should th e brom ine c o l o r re m a in , th e a d d i t i o n o f th e p o ta s * slum h y d ro x id e s o l u t i o n sh o u ld be c o n tin u e d u n t i l th e y e llo w c o l o r p e r s i s t s * A f te r th e a d d i tio n s had been c o m p leted , th e re * a c t i o n m ix tu re was c o o led t o *20 to *15°#

A c o p io u s p ro *

e i p i t a t e s e p a r a te d from t h e r e a c t i o n m ix tu re and was

00

fto lle & tM m

a filte r*

fli® p r e c i p i t a t e was t r i e d in. a i r a t

room te m p e r a tu r e f o r tw e n ty - f o u r h o u rs* The d r ie d c ru d e p r o d u e t was r e o r y s ta l li& e d fro® h o t* p u r i f i e d chloroform .*

P o ta ssiu m brom ide* w hioh was

p r e s e n t a s an im p u r ity i n th e c ru d e p r o d u c t, was removed by f i l t e r i n g th e h o t c h lo ro fo rm s o lu tio n * c o o le d t o -EG t o -10®*

The f i l t r a t e was

The N-bromo&eetamid© was c o l l e c t e d

on a f i l t e r and d r ie d in a i r a t room te m p e ra tu re *

The

y i e l d w as £41 g . ( 0 8 * a ^ ) * m.p* 105-100°* N -Brom o&eetasiide decom poses in w a te r a t room tem ­ p e r a tu r e *

C o n seq u en tly * d u rin g th e summer months when th e

m o is tu re c o n te n t o f t h e atm o sp h ere I s high* i t can n o t be d r ie d in a i r *

M oreover* a tte m p ts t o dry i t i n an oven r e ­

s u l t e d i n d e c o m p o s itio n .

U nder th e s e c o n d i t i o n s , th e f o l ­

lo w in g p ro c e d u re proved t o be an e f f i c i e n t ' method f o r d ry in g b o th th e cru d e and r e c r y s t a l l l a e d p ro d u ct* A G o e r 's p o r c e l a in lie . 3 Buchner fu n n e l co n ­ t a i n i n g th e p ro d u c t was f i t t e d t o a s u c tio n f la s h *

A sec­

ond C o e r 's p o r c e l a in No* 3 Buchner fu n n e l was in v e r te d and p la c e d on to p o f t h e f i r s t fu n n el*

The ju n c tu r e o f th e

two f u n n e ls wa© s e a le d w ith a ru b b e r sle e v e * w as c u t from an a u to m o b ile t i r e im i e r t u b e ) *

(The s le e v e The stem o f

t h e second B uchner f u n n e l was co n n ected by ru b b e r tu b in g t o a d r y in g to w e r c o n ta in in g c a lc iu m c h lo rid e *

I n t h i s manner

61 d ry a i r was drawn- th r o u g h t h e p r o d u c t by means o f a w a te r a s p ira to r*

fh© d r i e d M * bromo&aeiami&e was s to r e d l a a

vacuum a e e l c a t o r c o n ta in in g p o ta s s iu m h y d ro x id e p e l l e t s #

F o u r © o les o f oootam ido ( 236 g») and £00 ml# o f w a te r w ere p la c e d i n a 1 I # , tfcr#e*xi»cfce& round b ottom

flm&k e q u ip p e d w ith a m e c h a n ic a l s t i r r e r # s t a r t e d and t h e m ix tu re s e a le d t o 0°#

f h e s t i r r e r was

A s o l u t i o n o f 160 g*

o f sodium h y d ro x id e d is s o lv e d i n ZBO ml# o f w a te r was c o o le d

o to 0 #

A s m a ll amount { a b o u t 4 m l*) o f t h e b a s i s s o l u t i o n

w as added t o t h e r e a c t i o n m ix tu r e #

fh m

c h l o r i n e w as in tr o *

dueed s lo w ly k e e p in g t h e te m p e r a tu r e o f t h e m ix tu r e b elow o § « from tim e t o t im e a s m a ll amount o f t h e sodium hy­ d r o x id e s o l u t i o n was added s o t h a t th e r e a c t i o n m ix tu r e r e *

rsained b a s ic t o litm u s * When th e m ix tu re became s e m i - s o l i d * t h e s o l i d was

removed by f i l t r a t i o n and th e f i l t r a t e r e tu r n e d t o t h e re * a c t i o n v e s s e l*

t h e a d d i t i o n s w ere c o n tin u e d u n t i l th e m ix*

t u r e was n e u t r a l t o lit m u s * t o *1 5 °#

A w h it e s o l i d

The s o l u t i o n was th e n c o o le d

s e p a r a te d from t h e r e a c t i o n m ix­

t u r e and w as c o l l e c t e d on a f i l t e r #

R e c r y s t a l l i s a t i o n from,

benaene g a v e 31 0 * 0 g* (8E *9$) o f i'S -ch lo ro ao etam id e, m*p* 10V-1 0 8 ° ,

J. etre&m of dry chlorine was directed to the sur­ face of molten tin *

The gaseous* anhydrous stannic ehlos>

14o wm condensed*. co llected ana re d is tille d * b.p# 1M°. p r e p a r a t i o n o f t r a n s r S t l l b e n e (64)

fra n e -d tllb e n e was prepared by* the reduction of ben&oin using a slfu^mer-aury amalgam, and hydrochloric acid* 1 54*5$ y ie ld was obtained, m«p. 12B-1M0. 4 q1 ! (.jlfifr.. f h i e mold woo p re p a re d by c o n d e n s a tio n o f b en sol&ofty&e and p h e n y la o e tte a c id in t h e p re s e n c e o f a c e t i c a n h y d rid e and .t£ le th y lo s4 & o « P r e p a r a t i o n o fr

The y i e l d woo dd#dj»i ®*p. 1?2°. IM X

e i s * 8 t i l h e m was p re p a re d by- th e d e c a r b o x y la tio n o f a lp h a * p h e n y l* c ln n a m le a o id in t h e p re s e n c e o f co p p er c h ro m ite and q u in o lin e #

A y i e l d o f 62*5$ o f e l e - o t i l b e n e

was o b ta in e d ,, b*f* XM«456'° {10*11 mm.)* F re n a ra tio n

of l^lrmo-E-Ghloro-Ith&ne

I n t o a 1 1 . , th re e * n e a k e d round bottom f l a s k equ ip p ed w ith a m e c h a n ic a l s t i r r e r wers placed.. 126. .ml* o f c o n c e n tr a te d (B7%) h y d r o c h lo r ic a c id and 126 m l. o f w a te r., f h e s t i r r e r was s t a r t e d and th e a c id s o l u t i o n was co o led

m

t o «*00 *

i f b y i e n e and.

f t g* o f l^ b ro m o ae ata m id e w ere th e n

in tr o d u c e d t o t h e r e a c t i o n v e s s e l slo w ly and s im u lta n e o u e ly * I f lie IfriirQM&Getaml&e was added p o r tio n - w is e a t a r a t e such t h a t e n l y .l e e & l c o n c e n tr a t io n s o f brom ine w ere o b serv ed by M l# * } * t h e s t i r r i n g was d isco n tin u ed a f t e r th e r e a c tio n m ixtu re became a l i g h t y e llo w e e lo r and two liq u id la y e r s formed*

f h e m ixtu re was p laced in a sep a ra to ry funnel*

t h e w ater la y e r was removed,and e x tr a c te d w ith two 100 ml* p o r tio n s o f e th e r *

The crude bromeohl®roethane and t h e

e t h e r ex tra ct© w ere combined* washed tw ic e w ith 000 ml* p o r tio n s o f w ater; tw ic e w ith £50 ml* portion© o f 8% sodium b ic a r b o n a te ; and th r e e tim es w ith g§0 ml* p o r tio n s o f w ater*

The e th e r s o lu t io n was then d ried w ith s a l *

oium s u lf a t e * The e t h e r was rem oved by h e a tin g m a steam b a th * .

The r e s id u e was f r a c t i o n a l l y d i s t i l l e d w ith a T ig -

yeux #blumn»

e th y le n e feremoehlorl&e was o b ta in e d in 51*8-%

y ie ld * b .p * lOfi»X0&° ( a t 746*748 to m e te r )% n ^ % 1*4920*

&£% 1*703 ( g r a v l -

T hese v a lu e s a r e In good agreem ent

w ith th e v a l u e s r e p o r te d i n l i t e r a t u r e (8 * 0 4 .2 9 )* The a d d i t i o n o f e th y le n e t o a c h lo ro fo rm s o l u t i o n o f ft-brom ofteetam ld* t o w hich g aseous h y d r o c h lo r ic a c id had been added r e s u l t e d in 41% y i e l d o f e th y le n e dibrom ide, b .p * 1 0 8 -1 5 1 ° .

@4 ffe* gijN tttftM em * a d d i t i o n o f g m m m

fe ^ tro e h ie ri©

m i 4 and e th y le n e t o a c h lo ro fo rm e o l a t i o n o f {?*©?&*&*©*t * amid© gat© a &0#£?£ f l o l d o f a e©mpound c o n ta in in g brom ine and c h l o r i n e , b*p. 1O 4-1080 ; d a s 4 1*788 ( g r a v ito m e te r ) . f M s p r o d u c t wa© p e fra o ilo n & te ii and th e f r a c t i o n whoa© t o l l i n g p o i n t w m 1 0 6 -1 0 ?° had a s p e c i f i c g r a v ity o f 1 .7 4 S 25/ 4 * An *the?*$*feromo*e©t&mi&© m ix tu re was c o o le d t o o

0 *

G aseous h y d r o c h lo r ic a c id and e th y le n e war© sim u l­

ta n e o u s ly p a s s e d i n t o t h i s m ixture.*

B l e t i l l a t i o n , u s in g a

T i g r o w column* gat© no f r a c t i o n in t h e e th y le n e bromoc h l o r i d e rang® (104*108°)*

Ith y le n ® d ib ro m id e was o b ta in e d *

b u t th e f i e l d was n o t d eterm in ed * Q n e -h a if o f a g l a c i a l a c e t i c a c id s o l u t i o n o f l i t h i u m c h l o r i d e ( 0 .8 m ole) was added t o a m ix tu re o f g l a o l a l n o e t ic a c id and Nwhromoaoetamld© (0*4 m ole)*

fh® r e ­

m a in d er o f th e lit h iu m c h l o r id e s o l u t i o n was added w h ile e th y le n e w as b e in g p a sse d I n to th e r e a c t io n m ix tu re * T hie o r e a c t i o n was c a r r i e d o u t a t O'* t h e a d d i tio n o f e th y le n e w as c o n tin u e d u n t i l t h e r e a c tio n m ix tu re was c o lo r le s s * i

A f t e r th e a d d i t i o n s wey© com pleted* th e m ix tu re was washed w ith w a te r and e x t r a c t e d w ith lo w - b o ilin g l l g r o l n *

£he

11g r o in e x t r a c t was d r ie d w ith ca lciu m s u l f a t e and th e i i g r o l n removed by h e a tin g on th e steam b ath * d i s t i l l e d th ro u g h a T ig re u x column*

f h e r e s id u e was

^he fo llo w in g aom?QUnds

5S

» •» # o b ta in e d :!

lOT*}*

9*9

&*0 g* o f e th y le n e bromoahXorid© fb*-p« 1G&*

"1 # of ethylene

41

bromide (b*p*

-

1 1 1 1259

°} $ $*d g*

of to t aWbr$M#t hylM «t ate {&#?.» 100*16#)*

I n t o a. E l« .t th r e e - n e c k e d f l a s k eq u ip p ed w ith a e t i r r e r war® p la c e d 378 ml* c o n c e n tr a te d (37$) h y d r o c h lo r ic a®id and 370 ml* w a te r#

fh® f l a s k was p la c e d i n an [email protected]

s a l t b ath # t h e s t i r r e r s t a r t e d ana t h e m ix tu re c o o led t o *5°#

One and a h a l f m oles (156 g*) o f s ty r e n e was p la c e d

i n a d ro p p in g fu n n e l and added slo w ly t o th e m ix tu re#

At

t h e same tim e* one and a h a l f m oles (£07 g*} o f K -brom ea c e fa m ld e was added p o rtlo n « w ie e a t su c h a r a t e t h a t o n ly l o c a l c o n c e n tr a t io n s o f brom ine w ere o b se rv e d by c o l o r and t h e te m p e r a tu r e o f th e r e a c t i o n m ix tu re rem ained betw een 0 ° and - i ° #

A fter the additions were completed* the so lu tio n was placed In a separatory funnel and the water layer was removed and extracted twice with 100 ml* portion© of ether* fhe ether and styrene portion© were combined* washed with sodium bicarbonate* then water and. dried with calcium sulfate*, fhe eth er was removed by heating on the steam bath*

ffee residue was fra c tio n a lly d is tille d under

m

diminished p r a s t i i i *

On© hundred and nineteen gram s of

produet i M ^ o f theory) mm doll©©ted a t •f g**9t° and 3*8 mm#

or 110**X14° and 7 mm# t o r a n a ly tic a l purpose®, the fra c tio n whose to llin g po in t was 1X&**113° ( a t 7 ism*) mm meed* P h y s ic a l a o n eta o ta s d g% 1*49? ( phonom eter)

*?% 1*6790t »*°© X*§770f

*

Analyses t a) O&rfcofl^hydrogen* Calculated for QU Ml202Mtt

§* ****** s * *****

Founds

0# 43#7 fs I , 6 * 7 7 ,

fc) total halogen (modified Stepanow) i Calculated for O-j^I^gOXBrt 0*0407 g« foundi 0*0270 g*)

0*0401 g« (wel^ti of samplej

fh© total halogen was calculated in the

following manneri w t» cample

x 5S&,i g .^ |A.gAl£S> +w t» ©ample x

=

wt* '© liver halide* ) IB r*

B ep eated preoe& ure "A11 u s in g 4B0 ml* o f 11$

One ml* o f a l i q u i d was s o l l s s t e d a t 110-116'" (8 mm*)

but" i t did not co n ta in c h lo r in e * I)

B ep eated p ro c e d u re f*Aw em ploying 180 ml* o f

% 0 HBr and 7*0 g* (#068 m oles) o f p o ta ss iu m brom ide*

A gain

o n ly s ty r e n e dlbrom ld© was produced*

I)

A S o lu tio n oonai s t in g o f 355»S g . (O.Efi raolss)

o f K -ch loroaoetam id e d ia s o lv s d in 126 m l. o f w ater was p laced

&A a 800 m l* , th re e -m e c k e d ro u n d b o tto m f l a s k eq u ip p ed w ith To t h i s m ix tu re was added 88 ml* ( 0*24 m oles)

a s tirre r* o f s ty r e n e * t o * 1 8 £ » l §4° (25*9 g*)» W ater was added to t h e cton*a$uoeu8 la y e r #

^h e

m ix tu re was s t i r r e d r ig o r o u s l y w h ile feeing co o led in an [email protected] 'bath*

A p r e c i p i t a t e form ed and was c o l l e c t e d on a

f i l t e r * n*p« 1SG*X8B° (£5*4 g*)*

Iteorystallisatien w as acco m p lish ed by d i s s o l v i n g t h e c ru d e p r o d u c t i n h o t 98$ e t h y l a lc o h o l#

[email protected] was

added u n t i l t h e warm a l c o h o li c s o l u t i o n became cloudy*

Gaoling to £0° p ro d u ced the f i r s t c ro p o f c r y s t a l s *

M~

ai t i o n o f w a te r t o th e f i l t r a t e from t h e f i r s t c ro p £ol« low ed fey c o o lin g In an i c e b a th p ro d u ced a seco n d cro p o f c ry s ta ls * f h e c ru d e p r o d u c ts w ere f r a c t i o n a l l y r e c r y s t a l * l i g e d tw ic e t o y i e l d 19*$ g* {6£#?$) o f alpha*brom o*feeta* o h lo ro h y d ro o in n a m io ac id # m*p* 140*181° ( d e e , }« A n a ly sis* B# 3,04*

Founds

C a lc u la te d f o r G^HgC^Cl Brs

0 t 40*89;

I# 3*G£#

0# 40*95;

f© a s o lu t io n o f g«X g« (0*05 mole) o f ©odium h yd roxid e in 17 ml* o f 95$ e th y l a lc o h o l and 11 ml* o f w a ter was added o v er a p erio d o f th ree-q u a rter© o f

m hour

♦ g* (0«0887 mole) o f alpha**ferom©«feeta-chlor©hydrooinnami© a cid *

During th e a d d itio n and fo r t h r e e hours t h e r e a f t e r

th e m ixtu re was s t ir r e d a t 5 0 -6 0 °, A fte r th e h e a tin g and s t i r r i n g were com p leted f t h e m ixture was co o led to room tem perature and .d ilu te d w ith 500 ml* o f water#

The d ilu t e m ixture was made a cid to

litm u s w ith d i l u t e h y d r o ch lo ric acid*

C ooling in an i c e

hath and adding 3 -8 ml* o f d ilu t e h y d r o ch lo ric a o l i caused a w h ite © olid t o sep a ra te from th e m ixture*

The p r e c ip it a t e

was c o l le c t e d on a f i l t e r and d ried in a ir a t room tempera­ tu r e*

The crude y ie ld o f &lpha*fc?Qmoelnna&d