A-Methyl Cinnamaldehyde Synthesis

 

Patented Dec. 21,

1937

UNITED STATES

2,102.965 PATENT OFFICE

2,102,965

M A N U F A C T U R E o f UN S A T U R A T E D

ALDE

H Y D E S

Christian Meuly,

Water

assignor to E.

-

Brunswick, N.J.,

New

I . d u P o n t d e N e m o u r s & Com pany, Wilmington, Del, a c o r p o r a t i o n of Dela

ware

N o D r a w. .i. n g S.e rA ip ap ll iNc oa .t i o5 n, 4 A1 p5 r i l

20, 1936,

...

his invention

5

relates

14 Claims. (CI. 260-136)

to t h e ma n uf a c t ur e of

a l d e h y d e s . More particularly, this...invention r e lates to t h e synthesis of u n s a t u r a t e d aldehydes, w h e r e i n an a l d e h y d e o f t h e g e n e r a l formula R1-CH2-CHO s condensed w i t h an aldehyde o f the general formula R2-CHO, in the presence of alkaline condensing agents according to t h e general Scheme:

()

5

R-CH3OHC-CHO-R-CH=C-CHO. l, k

R 1 and R 2 b e i n g alkyl, aralkyl o r aryl radicals. It i s an object of this i n v e n t i o n to p r o v i d e an i m p r o v e d process for effecting syntheses of the ia nb vo ev net ig oe n e rt ao l ptry op ve i. d e I t a i sp ra o fc ue sr st h ef ro r o bs jy en ct th eosfi zt ih ni gs unsaturated aldehydes, characterized by hig h yields and improved overall efficiency. I t i s a further object of this invention to produ ce novel u n s a t u r a t e d a l d e h y d e s . O t h e r and f u r t h e r im p o r t a n t o b j e c t s of t h i s i n v e n t i o n will appear a s the description proceeds. It h a s b een c u s t o m a r y in the art to carry out the reaction a b o v e indicated by starting with t h e f r e e aldehydes i n pure form. This n e c e s s i t a t e d t h e steps of preparing and isolating t h e i n i t i a l m a t e r i a l i n pure f o r m . M o r e o v e r , the y i e l d has

not always been s a t i s f a c t o r y due t o the formation of a l d o l condensation products a n d various resinous by-products. . . . . In U. S. Patent No. 1,716,822, it has been pro posed to solve the l a t t e r d i f f i c u l t y b y carrying out t h e r e a c t i o n i n an a l coh ol i c medium c o n t a i n i n g l e s s t h a n half of i t s weight of water; in other . .

wI no r td hs ,e aa cl tc uo ah lo l e xo fa m ap tl e lse assett 6f 6o .r t7 h i cn o ns ca ei nd t pr aa tt ie on nt ., the use of 9 6 alcohol to absolute alcohol is pre

Scribed.

: )

.

.

.

I n British P a t e n t . N o . 2 8 4 . 4 5 8 and Ge r ma n Patent N o . 5 5 3 , 0 3 7 w h i c h a r e t h e c o r r e s p o n d i n g foreign duplicates of U. S. P. 1,716,822, it h a s b e e n emphasized t h a t t h e s u c c e s s o f t h e r e a c t i o n d e p e n d s u p o n t h e m a i n t e n a n c e of a single p h a s e throughout the r e a c t i o n . This c o n d i t i o n i s b rou g ht ab ou t b y the use of substantially a n h y d r o u s alc o h o l and of caustic pot a sh, b o t h o f

w h i c h a r e e x p e n s i v e . M o r e o v e r , t h e y i e l d s ob t a i n a b l e b y the p r o c e s s of t h i s p a t e n t a r e s t i l l f a r

from t h e t h e o r e t i c a l . ... N o w , I have found that the condensation o f t w o a l d e h y d e s i n t h e p r e s e n c e o f a n a l k a l i n e con 5

d e n s i n g a g e n t p r o c e e d s w i t h an u n u s u a l d e g r e e of e f f i c i e n c y and ubstantially w i t h o u t t h e forma t i o n o f b y - p r o d u c t s , if a t l e a s t one o f the a l d e

caustic alkali wi l l decompose I have found, however, that t h e a l d e h y d e t h u s liberated is in a specially As

W

-

aldehyde.

is we ll

an aldehyde

known,

bisulfite.

reactive or nascent form, w h i c h condenses ly

of

rapid

with the other aldehyde, without the formation a l d o l by-products. This accentuated r e a c t i v i t y

5

may e o b s e r v e d n o t o n l y w h e n t h e a l d e h y d e b i t h e one which i s d e s i g n e d to f u r n i s h t h e

sulfite is

atom

the condensation above formulated c o m p o u n d d e s i g n a t e d a s R-CHO), b u t also when i t i s t h e o n e d e s i g n e d t o f u r n i s h

O

(that

in

the

is,

the H

group

(designated

above

as

20

R1-CH2-CHO).

E v i d e n t l y , t h e d e c o m p o s i t i o n o f t h e b i s u l f i t e com t h e alkali d o e s n o t liberate s i m p l y t h e aldehyde i n f r e e CHO form, but generates t i n a v e r y special, reactive f o r m ; p e r h a p s in th e form. pound by of

its

h y d r a t e (R-CH(OH)2).

It will

theory

be

understood,

i s advanced

plaining this invention better, to

desire

but

b e limited thereby.

I t i s an advantage

that

however,

latter

the

merely for the s a k e of that I

ex

do not

30

of my novel process that the

aldehyde i s never p r e s e n t i n f r e e form except i n . v e r y s m a l l a m o u n t s . I f t h i s a l d e h y d e c o n t a i n s a 35 CH2 g r o u p n e x t t o t h e C O g r o u p t h e d a n g e r o f

undesired self-condensation is eliminated, be c a u s e t h e r e i s p r e s e n t a t e v e r y moment a l a r g e excess of t he sec o n d aldehy de. ... As lk alin e m e d i u r n , o n e nay e l e c t a n a d u e o u s , a l c o h o l i c o r aqueous-aicoholic s o l u t i o n o f a s u i t a b l e a l k a l i n e c o n d e n s i n g a g e n t . A w o - p h a s e me dum c o n s i s t i n g o f a n a q u e o u s s o l u t i o n o f the

40

agent with a water-immiscible organic I find that in my process the formation of t w o

alkaline diluent, phases

may a l s o b e e m p l o y e d .

in

the

reaction vessel

of the reaction is sequently,

I am

no

during the course

d e t r i m e n t to t h e yield;

at liberty to

employ

con

in a dilute

alcohol medium... s o d i u m hydroxide as alkaline c o n d e n s i n g a g e n t , i n p l a c e o f p o t a s s i u m hy d r o x i d e . T he

bears

The

election

a n economic

question,

of

caustic Soda, of course,

advantage.

which aldehyde s

to be

employed

h y d e s e m p l o y e d i s i n t h e f o r m o f i t s b i s u l f - i t .e eaa rsl ndteehdhey dbb eyi ss u el acf rio tene o pcm roi emc ppaocruoendsdi ,bd eywr iaal tl i opg rne son .ce er as lSs li yni cnbeveo lmgvooisnvtg I n m y p r e f e r r e d mode of p r o c e d u r e , a n alde in t e rme d ia t e conversion i n t o t h e b i s u l f i t e c o m h y d e b i s u l f i t e c o m p o u n d i s f e d g r a d u a l l y i n t o a p o u n d f o r the sake o f r e c o v e r y o r p u r i f i c a t i o n , s o l u t i o n of c a u s t i c alkali, w h i c h may or may not it is convenient to use as i n i t i a l material the 60 compound.

(30

contain a n o t h e r aldehyde. Where the alkaline if does not contain another aldehyde, the latter may b e fed i n simultaneously. Wi th th e f i r s t a l d e h y d e , either in t h e free -CHO o r m , o r in t he f o r m of a b i s u l f i t e c o m p o u n d . The s e c o n d 5 aldehyde may be the s a m e as the first, the re action i n that case being directed to w ar d self c o n d e n s a t i o n b e t w e e n t w o m o l e c u l e s of t h e same

solution

...

.

.

.

. .

.

 

2

2,102,965

c r u d e bisulfite p r o d u c t , this stage, without first dehyde f o r m . T h i s i s a d v a n t a g e o f my n o v e l

directly a s obt a i n e d at recovering the free al a particularly valuable p r o c e s s , b e c a u s e i t en

a b l e s t h e s y n t h e s i s t o proceed f r om C r u d e , a n d

alpha-amyl-cinnamic-aldehyde a n d 72 parts o f

.

...

Parts m e nt i one d are b y Weight, Eacample

5

1

aqueous-alcoholic caustic. Solution i s pre pared b y dissolving 3 2 parts of S o d i u m hydro xide i n 8 0 p a r t s o f water a n d 3 0 0 p a r t s o f m e t h a n o l . 8 5 p a r t s o f this solution a r e mixed w i t h 1 0 6 p a r t s o f b e n z a l d e h y d e . I n t o t h i s mixture a r e added s i m u l t a n e o u s l y o v e r a p e r i o d o f 4 hours a t ordi nary temperature the remainder o f t h e aqueous alcoholic caustic solution and 1 1 5 parts of C r u d e n - o c t y l i c a l d e h y d e b i s u l f i t e c o m p o u n d i n e l y poW d e r e d , a s m a y b e o b t a i n e d , f o r i n s t a n c e , b y treat i n g a c c o r d i n g to t h e methods k n o w n t o t h e art, An

20

crude n - o c t y l aldehyde with a s l i g h t e x c e s s o f sodium bisulfite a n d washing the p r e c i p i t a t e o f crude n - o c t y l i c aldehyde bisulf ite c o m p o u n d w i t h

30

35

40

i m p u r i t i e s hsao vl ev e nb te eonn ra e mf iolvt ee rd u an tni dl ad lrl y i n g t h e m o i s t c r y s t a l s . When t h e a d d i t i o n i s c o m p l e t e t h e r e a c t i o n m a s s i s s t i r r e d for o n e - h a l f h o u r l o n g e r at room t e m p e r a t u r e . 1 , 000 p a r t s o f C o ld a n organic

Organic

W a t e r a r e a d d e d a n d t h e o i l y c o n d e n s a t i o n prod uct is i s o l a t e d a n d distil l ed in a V a cu u m . T h e r e is o b t a i n e d , b e s i d e s r e c o v e r e d benzaldehyde and 3 p a r t s of r e s i d u e (a non-distillable v i s c o u s oil), 7 1 p a r t s o f alpha-hexyl-cinnamic-aldehyde o f

excellent purity. The e a c t i o n i n v o l v e d

a b o v e may e r e pr e s e nt e d b y the following equation:

-eno ng Hoi s o nso rsi o n

{

-->

{X-CH=-cho+Noiso-tailso

t h e 1 1 5 p a r ts o f n - o c t y l al dehyde-bisulfite c o m p o u n d are replaced b y the e q u i v a l e n t o f 1 7 4 p a r ts o f t h e m o i s t c r y s t a l s a s

obtained

c o m p o u n d with

b y washing

the

crude

bisulfite

methanol Without Subsequent drying, i d e n t i c a l r e s u l t s are obtained. The n e t h a n o l o f E x p e r i n e n t 2 may b e re placed b y other solvents such as ethanol, ethyl 6 0 e t h e r o r b e n z o l , w i t h o u t changing t h e results. Eacample 3

solution is

pr e pa r e d b y d i s s o l v i n g 8 0 parts potassium hydroxide n 3 0 0 p a r t s o f Water a n d 500 p a r t s o f methanol. 200 p a r t s o f t h i s s o l u t i o n are added t o 150 parts o f benzaldehyde. O ver a pe riod of 3 h o u r s there i s gr a d u a lly a d d e d at 2 5 to 3 0 ° C. t h e r e m a i n i n g 6 8 0 pa r t s o f t h e a l k a l i s o l u t i o n a n d simultaneously t h e equivalent of 70 7 9 p a r t s o f n - h e p t y l i c aldehyde i n the form of its sodium bisulfite compound. T h e r e a c t i o n maSS i s d i l u t e d w i t h 1 5 0 0 p a r t s w a t e r a n d t h e reac t i o n pr od u c t i s o l a t e d a c c o r d i n g t o k n o w n meth o d s . Aft e r p u r i f i c a t i o n b y d i s t i l l a t i o n i n a Vacu 7 5 u m , there is obtained 1 2 0 t o 1 2 4 p a r t s o f p ure

A

.

.--

5

ÖH,CHCHCHCH,

Eacample

4

n h e pI ft ,y li in c Ea xl ad em hp yldee 3 ,s tr eh pe l baicseu dl f bi yt e t hceo bmips ou luf ni tde ocf on pound which i s e q u i v a l e n t to 1 0 6 p a r t s o f c i t r o n e l l a l , a n e w c o m p o u n d i s obtained in good yield, having a boiling p o i n t o f 1 2 9 to 1 3 1 at 2 mm. pressure a n d a r e f r a c t i v e indeX 20 o f 1 . 5 4 3 5 a n d p o s s e s s i n g probably the formula:

gh,

pH,

- C H= c - C H - C H - C H = C - C i s CHO

This

erties

compound

appears to

have

aluable

for t h e m a n u f a c t u r e o f p e r f u m e s .

prop

Eacomple 5

A

s o l u t i o n is

prepared f r o m 9 0 parts o f s o 450 p a r t s o f water a n d 7 5 0 p a r t s a l c o h o l . 300 p a r t s o f t h i s mixture a r e

dium hydroxide

of ethyl

a d d e d to 2 6 6 g n . of c u m i n i c a l d e h y d e a n d over a p e r i o d o f 3 hours are added a t ordinary tem p e r a t u r e , s i m u l t a n e o u s l y , t h e remaining 9 9 0 p a r t s o f a l k a l i s o l u t i o n a n d 2 4 3 p a r t s o f f i n e l y pow dered bisulfite c o m p o u n d o f propionic aldehyde ( e q u i v a l e n t to 8 7 p a r t s o f p r o p i o n i c a l d e h y d e ) . When t h e a d d i t i o n i s c o m p l e t e , t h e r e a c t i o n m a s s

O

3 5

kept for one- h alf h o u r longer at 2 0 to 30° C. A f t e r diluting with 2,000 parts of cold water, most o f the r e a c t i o n product s e p a r a t e s out a s a yellowish oil. A f t e r distilling i n a vacuum. ' there is obtained, for instance, besides 10 parts of residue, 1 0 0 p a r t s of unchanged c u m i n i c a l d e h y d e a nd 202 p a r t s o f para-isopropyl-alpha-methyl cinnamic aldehy de having a b o i l i n g p o i n t o f 1 1 5 is

to

120°

C.

at

f

2 mm.

mercury.

During the course of the addition, the reaction mass s e p a r a t e s i n t o two distinct layers: an up per o i l y on e containing m o s t of the reaction prod the inorganic

If, in Example 1,

may be

.

l u c t , a n d a lower aqueous one containing most of

CoE13

Eacample 2

55

.

-

materials.

l a rW iptr ho oc ue td u rl ie m, i t ih neg fmo yl l o wn iv ne gn t ei xo na mtpol ea sn ya rp ea r gt i cv eu ln t o i l l u s t r a t e my p r e f e r r e d m o d e o f O p e r a t i o n .

O

.

Alpha-amyl-cinnamic a l d e h y d e m a y be repre s e n t e d b y t h e f o l l o w i n g formula

therefore cheaper, material. I f desired, b o t h a l d e h y d e s m a y b e employed a s b i s ul f i t es , t he re b y re d u cin g t he cost of b ot h ini tial

.

b e n z a l d e h y d e

salts.

r e a c t i o n i n t h e above example resented b y the f o l l o w i n g equation: The

may

e

rep

re-(D-enouguo s o - s o n , i c - C D - o n l i n o -Na2SO3-2O Eacample

6

5

O

An q u e o u s - a l c o h o l i c S o l u t i o n o f potassium h y . d r o x i d e , i s prepared b y d i s s o l v i n g 1 2 6 p a r t s o f p o t a s si si u m h y d r o x i d e i n 4 5 0 p a r t s 300 parts o f methanol. 1 5 0 p a r t s

o f water and o f t h i s mix

t u r e a r e added t o 3 5 0 p a r t s o f m e t h a n o l . Over a period o f four hours there are added s i m u l t a n e o u s l y a t 2 5 C . (1) t h e remaining 7 2 6 p a r t s o f a l k a l i s o l u t i o n , ( 2 ) 1 3 1 p a r t s o f p r o p i o n i c al dp eohuynd de , o af n Cdu n (n3 i) n i 5c 0 a5 l pd ae rh ty sd eo f sc ur cu hd e a bsi smu laf yi t eb ecoobm t a i n e d w h e n c r u d e cu cu m i n i c a l d e h y d e i s p u r i f i e d b y converting i t

i n t o its bisulfite

c o m p o u n d ac

C O r d i n g t o t h e p r o c e s s e s w e l l known t o t h o s e s k i l l e d i n the a r t . A f t e r a d d i t i o n s are completed

(5.5

 

the reaction mixture

is

kept at ordinary

2,102,965

Its

tem

p e r a t u r e f o r 1 5 minutes l o n g e r . T h e r e a c t i o n product is f r a c t i o n a t e d under v a c u u m, a n d t h e r e is o b t a i n e d 6 0 p a r t s of c u m i n i c a l d e h y d e and 5 190 parts of p u r e para-isopropyl-alpha-methyl cinnamic a l d e h y d e . Eacample

may

be replaced by an equivalent

of sodium hydroxide.

Eacample

of

A olution is

prepared

by

amount

8 dissolving 140 parts

o f water a n d so lutio n 240 p a r t s a r e p l a c e d in t h e r e a c t i o n vessel. To this

s od i u m hydroxide i n 440 parts Of this 6 6 0 parts of methanol.

(1)

the

equivalent to 148 parts of cuminic aldehyde

and

are added simultaneously over 4 hours

remaining a mixture

1,000 p a r t s of alkali solution and (2) o f the r e s p e c t i v e bisulfite c o m p o u n d s

to 70

3

parts o f p r o p i o n i c a l d e h y d e . After th e addition is complete, the reaction mix t ur e i s d i l u t e d w i t h 1 , 0 0 0 p a r t s o f w a t e r . The o i l y r e action pr od u ct is p u r i f i e d b y v a c u u m d i s t i l l a t i o n and a good y i el d o f pure para-isopropyl-alpha

5 methyl-cinnamic-aldehyde is obtained. Eacample

9 dissolving

A o l u t i o n is prepared b y 3 2 parts o f so d i u m hydroxide i n 150 p arts of water a n d i 0 0 40 p a r t s o f methanol. A reaction v e s s e l i s cha r g e d with 50 parts o f t h i s a l k a l i n e S o l u t i o n a n d W i t h 1 0 p a r t s o f pro p i o n i c aldehyde i n 1 0 0 p a r t s o f methanol. To t h i s mixture is added simultaneously over 2 h o u r s a t r o o m t e m p e r a t u r e t h e r e s t o f t h e al k a l i n e s o l u t i o n , 3 9 parts of propionic aldehyde a n d 57 p a r t s o f h e p t y l i c aldehyde, the l a t t e r be i n g i n t h e f o r m o f i t s b i s u l f i t e c o m p o u n d . T he r e a c t i o n mass upon f r a c t i o n a t i o n yields, b e s i d e s as lodmeeh yud ne c, h amnogsetdl yp r otphieo n ip cr oaplidoenhiycd-ea al dn ed h hy edpet -y hl ei cp t y l i c - a l d e h y d e c o n d e n sa sa t i o n p r o d u c t b o i l i n g a t 7 6 t o 8 2 ° C . a t 3 m m . o f m e r c u r y a b s o l u t e pres 5

Su'e.

two

r e a c t i o n p r o d u c t is p r o b a b l y a mixture o f isomeric aldehydes of the following for

he

m u la s :

-:

CH - C=CH - CH .C. is

CH-CH-CH=C-C. is and

Ho

Eacample

A

o l u t i o n is

10

Ho

p r e p a r e d f r o m 9 2 parts potassium

h y d r o x i d e , 2 7 6 parts w a t e r and 1 8 4 parts m e t h a n o l . I n t o th e reaction v e s s e l a r e p l a c e d 3 0 0 p a r t s methanol and 1 1 0 p a r t s o f t h e above alkali s o l u t i o n . At room temperature t h e r e a r e added s i m u l t a n e o u s l y o v e r two h o u r s (1) t h e rest o f t h e alkali solution, (2) 80 p a r t s propionic alde h y d e a n d ( 3 ) 2 8 2 p a r t s o f t h e b i s u l p h i t e pcr o om d pound of piperonal. From the reaction u c t a r e isolated by fractional distillation 6 0 p a r t s p i p e r o n a l and 1 0 5 p a r t s a l p h a - p i p e r o n y l i d e n e 55

p r o p i o n i c aldehyde which melting at 6 4 to 65° C.

is

a p a l e y e l l o w Solid, :

{D-on--cro that

5

CH3

details of pr o a r i a t i o n a n d m o di f i c a t i o n w i t h o u t d e p a r t i n g from t h e spirit o f t h i s ip nl vo ey n st ioodni. u m T hh yu ds r, o wx hi id le e a In dh ap vo et a ps rseif ue mr rh ey dd rt oo x iem de, si n g a g e n t c u s t o m a r i l y a n y o t h e r a l k a l i n e c o n d e n si em ployed i n the a r t f o r t h i s type o f r e a c t i o n , f o r i n s t a n c e a l k a l i n e e a r t h h y d r o x i d e s , may b e It will

If the initial 8 7 6 parts of aqueous-alcoholic 9 caustic solution o f Example 6 a r e r e p l a c e d by ap an r tasq u oe fo u pso ts ao sl ustiiuomn phry ed pr ao rx ei dd e b iy n d 6i s0 s0 o l pv ai nr gt s 1 4o 0f wa t e r a n d c a r r y i n g o u t t h e c o n d e n s a t i o n a s de s c r i b e d i n Example 6 , a similarly good yield o f

droxide

may

HC O

7

para-isopropyl-alpha-methyl cinnamic aldehyde is o b t a i n e d , although the r a t i o o f recovered C u minic aldehyde is h i g h e r . T h e potassium hy

structure

lowing formula:

3 be represented b y the fol

b e understood

cedure are

...

usceptible of

wide

the

used.

T he i s u l f i t e c o m p o u n d m a y b e i n t h e f o r m o f S o d i u m , p o t a s s i u m o r ammonium a l t . A s al ready i n d i c a t e d , i t need not b e p u r e . I n f a c t , t h e p r e f e r r e d method c o n s i s t s i n u s i n g t h e inter mediate products wh i c h are obtained i n the p r o c e s s o f p u r i f y i n g c r u d e a l d e h y d e s . The b i s u l f i t e c o m p o u n d s may c o n t a i n e x c e s s s o d i u m b i s u l f i t e ,

its

Water, or organic

20

Solvents.

ratio of reacting materials may be varied Within wide limits. As a rule, the aldehyde whi c h i s in free f o r m i s t o b e used i n a n e x c e s s , so as The

5

to c o m p l e t e l y c o n s u m e t h e m o r e v a l u a b l e b i s u l

c o m p o u n d . A easonable excess v a r i e s f r o m 0 t o 1 0 0 . T h e a l k a l i n e c o n d e n si si n g a g e n t i s 3 : ) u s u a l l y emplo yed i n such a quantity that a f t e r

fite

conversion of t h e alkali

bisulfite

there remains e n o u g h a l k a l i densation at r o o m temperature.

fite

of alkali per results.

mole

i n t o a l k a l i Sul

t o e f f e c t con 1 t o 2 moles

o f bisulfite generally gives

good

5

T h e p r e f e r r e d l i q u i d medium f o r t h e r e a c t i o n i s o n e i n w h i c h f r e e aldeh y de a n d b i s u l f i t e com p o u n d a r e b o t h S o l u b l e . T h i s i s usually a n a due o u s - a l c o h o l i c mixture, th e preferred a l c o h o l s be ing methanol, e t h a n o l , propanol, g l y c o l or mix

tures o f w a t e r miscible solvents. While t h e best c o n c e n t r a t i o n i s b e t w e e n 40 a n d 8 0 , the process is operative for all concentrations solvent

t o a n h y d r o u s s o l v e n t s , f o r instance b e n z o l , e t h y l e t h e r , a n d the like, provided the a l k a l i n e condensing agent is added i n the f or m of an aqueous o r a l c o h o l i c s o l u t i o n . T h e o r d e r o f mixing the m a t e r i a l s m a y b e from Water

Vt ao r iaeddd c to nh sei d bei rs au bl lf iy t, e tch eo mpproe uf en rd r ead n md e tc oh no dd e bn es ii nn gg a g e n t S g r a d u al l y t o t h e f r e e a l d e h y d e s o a s t o a v o i d t h e p r e s e n c e o f h i g h c o n c e n t r a t i o n s o f c on

densing agent in the reaction mass.

This

()

order,

h o w e v e r , may e a r i e d c o n s i d e r a b l y , f o r i n s t a n c e , i . b y a d d i ng the condensing agent t o a mixture of f r e e aldehyde and a l d e h y d e - b i s u l f i t e compound o r r e a c t i n g s i m u l t a n e o u s l y c o n d e n s i n g a g e n t , al

dehyde

and

aldehyde-bisulfite c o m p o u n d .

thesis,

although

T h e o p t i m u m temperature is about the sa me {{} a s has been customary i n t h e a r t f o r t h i s syn

w i d e r v a r i a t i o n is permissib le. 5 0 ° C . were t r i e d a n d or lower o n e s m ay be

Temperatures from 0 t o found s u c c e s s f u l . H i g h e r

found s a t i s f a c t o r y if the a m o u n t o f condensing a g e n t o r t h e t i m e a r e a d j u s t e d . T he u s u a l t i m e

to 5 hours. The additions s h o u l d b e s l o w enough to c a u s e c o m p l e t e reaction of t h e p r e v i o u s l y added bisulfite compounds, b e f o r e t h e

i s from 1

i n eTx ht ea di ds oi lt ai to in o. n

of the reaction product may like w i s e f o l l o w standard p r a c t i c e . T h e most c o n v e n i e n t W a y c o n s i s t s o f d i l u t i n g the r e a c t i o n mass

with water t o d i s s o l v e the inorganic s a l t s f o r m e d and

separating t h e insoluble

oily

condensation

()

 

4

product.

visable to went

like

For quantitative recovery,

2,102,965 ad a l i q u i d

it is

extract the m o t h e r l i q u o r With a S o i e t h e r o r b e n z o l . A n a l t e r n a t i v e method

c o n s i s t s o f di s ti l l i ng o f f the a l c o h o l i c S o l v e n t , u n p a r t i a l n e u t r a l i z a t i o n o f the reaction maSS,

der

5

if

necessary, followed b y separation or extraction o f t h e c o n d e n sa t i o n p r o d u c t .

The

above process

version of from the

()

may

any aldehyde

aliphatic,

b e a p p l i e d t o t h e con or pair of aldehydes

aromatic or inydroaromatic

ss eo r i ce sh,o sperno v pi odses de s sa et s l ae a sCt H 2o n eg r oo uf p t hi en 2a -l pdoeshi yt di eo sn ( t h e group CHO being counted as 1). It will

be understood from the preceding d i s I have p r o v i d e d a v e r y economical

cussion that

and e f f i c i e n t saturated

m e t h o d for the production of

aldehydes.

c o m m o n aldehydes

As is well known, are usually purified

v e r s i o n into their bisulfite

un less

the b y con

com p ounds , followed

b y liberation w i t h alkaline or acid agents. T h i s

5

l i b e r a t i o n always i n v o l v e s s o m e l o s s e s o f the s e n s i t i v e a l d e h y d e s due t o a t t a c k by the above mentioned a g e n t s . The liberated aldeh ydes t h e r e f o r e have o f t e n t o be f u r t h e r p u r i f i e d b y distillation. Ac c o rdi n g t o my n v e n t i o n , the

fractional

steps and losses l i b e r a t i o n a n d involved in distillation o f the a l d e h y d e are avoided, since decomposition and condensation are c a r r i e d cut i n the s a m e v e s s e l , e i t h e r simultaneously o r i n immediate Succes the

S.O.

...

()

F u r t h e r m o r e , my p r o c e s s i s c h a r a c t e r i z e d b y higher yields of the desired end-product, based o n t h e m o r e e x p e n s i v e o f t h e t w o a l d e h y d e s en ployed a s i n i t i a l material. I n c o m p u t i n g this yield as a n u m e r i c a l percentage, it s h o u l d b e borne i n m i n d t h a t the a v a i l a b l e q u a n t i t y o f a l d e h y d e in a g i v e n w e i g h t of bisulfite i s n o t that w h i c h t h e o r e t i c a l l y corresponds t o the f o i ' mula R.CHO.SO3Na, bu t t h a t q u a n t i t y which c o u l d b e r e c o v e r e d from the g i v e n Weight o f the bisulfite compound by employing know n i m e t h o d s of hydrolysis, as for instance by the aid of al k a i . T h i s q u a n t i t y i s g e n e r a l l y less than t h e theoretical

m a x i m um d u e

to

the

losses of

alde

a b o v e m e n t i o n e d . When t h i s a v a i l a b l e quanti ty i s u s e d a s a basis, my process leads to n e a r l y theoretical y i e l d s . I n a n y event, t h e yields b y m y p r o c e s s e x c e e d c o n s i d e r a b l y t h o s e men hyde

wt ih oince hd i in n i t she el f a cr tl ,a i imnsc lc uo dn is ni gd e rU a. b lS e. i Pm.p r1 o7 v1 e6 ,m8e2 n2 t, over the y i e l d s o f the a r t . In the claims below it w i l l b e understood that

the phrase “an unsaturated aldehyde of the series' refers to a c o n t a i n i n g i n its s t r u c t u r e the r a d i c a l

cinnamic aldehyde

( O - o n - - c hl o oo k e d

6 0 a n d w h i c h may t h e r e f o r e

substitution derivative of

compound

be upon cinnamic aldehyde;

medium and

condensing agent.

the presence of

an

alkaline

3 . T h e p r o c e s s o f producing an u n s a t u r a t e d a l d e h y d e , which c o m p r i s e s b r i n g i n g i n c o n t a c t , i n a q u e o u s - a l c o h o l i c m e d i u m an d i n the p r e s e n c e

o f an a l k a l i n e c o n d e n s i n g a g e n t , an a l d e h y d e CH2 CHO and an a l Containing the grouping

5

d e h y d e c o n t a i n i n g a -CHO r o u p , a t

of said

aldehydes being

fite compound.

a l 4d .e hTy hd ee ,

-

in

the form

least one o f its bisul

process of p r o d u c i n g a n unsaturated

which comprises f e e d i n g the b isu l f it e compound o f an aldehyde having a C H 2 group next t o the aldehyde r a d i c a l i n t o an aqueous a l c o h o l i c s o l u t i o n o f c a u s t i c alkali, and recover

i n g t h e r e a ct ct i o n p r o d u c t . 5 . T he p r o c e s s o f p r o d u c i n g a n u n s a t u r a t e d aldehyde, w h ich comprises feeding the bi s u l f i te c o m p o u n d o f a n a l d e h y d e h a v i n g a CH2 g r o u p

n e x t t o t h e al al d e h y d e r a d i c a l i n t o a n a q u e o u s a l c o h o l i c solution o f c a u s t i c alkali c o n t a i n i n g an aromatic a l d e h y d e , a n d r e c o v e r i n g the r e a c t i o n product.

6 . The p r o c e s s o f p r o d u c i n g a n u n s a t u r a t e d aldehyde, w h i c h comprises feeding the b i s u l f i t e

o f an a l d e h y d e and a t least one o t h e r o f s a i d aldehydes having a C H 2 n e x t t o t h e a l d e h y d e r a d i c a l , i n t o a n aqu e

compound

aldehyde,

group

one

ous-alcoholic Solution o f caustic alkali,

a n d re

covering the reaction product. 7. A process as i n claim 6 , the second a l d e hyde being l i k e w i s e i n the form o f a bisulfite Compound. 8 . T he p r o c e s s o f p r o d u c i n g a n u n s a t u r a t e d aldehyde, which comprises bringing i n t o c o n t a c t , i n a l i q u i d m e d i u m , a n a l i p h a t i c a l d e h y d e hav i n g a CH2 g r o u p n e x t t o t h e a l d e h y d e r a d i c a l a n d a n a r o m at at i c a l d e h y d e o f t h e b e n z e n e S e r i e s , i n the presence of a n alkaline c o n de n sin g agent, a t l e a s t o n e o f S a i d a l d e h y d e s b e i n g i n t h e f o r m 40 of its b isulf it e c o m p o u n d . 9 . A rocess as in claim 8 , the a l d e h y d e b i s u l f i t e b e i n g m i x e d g r a d u a l l y a n d i n S m a l l quan t it ie s wi t h the other materials. 1 0 . A rocess as i n claim 3 , the reaction b e i n g e f f e c t e d i n a me d i u r n of the g r o u p consisting o f Water, a l c o h o l , a n d mixtures of the two. 1 1 . The p r o c e s s o f p r o d u c i n g a n u n s a t u r a t e d aldehyde, w h ich comprises feeding the bisul

ff irt eo mc o3 m tp oo u1 n0 d c aorfb oann aatloi mp hsa thiac v ia nl gd eah yCd He 2h ga rv oi nu gp next t o t h e aldehyde r a d i c a l i n t o an aq ueo us a l c o h o l i c s o l u t i o n o f c a u s t i c a l k a l i containing an a l d e h y d e o f t h e b e n Z e e e r i e s , d i l u t i n g t h e re action m a s s wi t h W a t e r a n d recovering the f o r m e d

o i l y condensation product. 1 2 . T he p r o c e s s o f p r o d u c i n g

5 5

an unsaturated aldehyde, w h ich comprises feeding the bi s u l f i te

as a Said

phrase including, of course, c i n n a m i c aldeh yde itself.

I claim:

p r o c e s s of p r o d u c i n g an u n s a t u r a t e d al which c o m p r i s e s r e a c t i n g an a l d e h y d e bisulfite having a C H 2 g r ou p next t o the a l d e hyde radical w i t h an a r o m a t i c a l d e h y d e in a liquid medium and i n t h e p r e s e n c e o f an a l k a 1. The

dehyde,

l i n2 e. cTohned e np sr oi cn eg s as g eo nf t .p r o d u c i n g a n u n s a t u r a t e d

a l d e h y d e , which c o m p r i s e s r e a c t i n g two alde hydes o f which a t l e a s t one has a C H 2 group n e x t t o t h e CHO g r o u p , a nd o f which a t le a st one i s i n t h e form o f its bisulfite compound, i n

compound

o f citronellal into

an

aqueous-alcoholic

s o l u t i o n o f c a u s t i c a l k a l i containing be n z a l d e hyde, d i l u t i n g the r e a c t i o n mass with w a t e r , a n d recovering the o i l y condensation product. 1 3 . T h e condensation product o f c i t r o n e l l a l b i s u l f i t e and b e n z a l d e h y d e . 1 4 . The c o m p o u n d o f t h e

GH,

30

formula

pH,

-CH=C-CH-CH=CH-CH=C-ch. CEO

said compound being a liquid boiling at 1 2 9 t o 1 3 1 ° C . a t 2 mm. b s o l u t e p r e s s u r e .

about

WALTER C H R J S T I A N M E U L Y .

5