Патент USA US2572947

Patented Oct. 30, 1951
2,572,943
UNITED
PATENT tors-[cs
525723.13
,BRQDUCEHON 0F BIFUNCTIONAL CARBQNYL
COMPQUNDSIEBQM 1,4:DIQHL0R0BUF1‘ANE
Alfred L. Miller, .Summit, 1N. jJ_,, ,and "Bernard "H.
‘KI'QSS, moledmzQhio, assignors ‘to _Cela-n_e_se<Cor
vporation of ‘America, New YorkgN. *Y., a corpo
irationofDelawate
No Drawing. ApplicationApril'29, 1951.9,
Serial No. $10,556
vl
.,2=,Claims. (Cl. '260+601)
2
This invention relates to the preparation {Of
compounds containing an aldehyde group and
:halide,high temperatures of about 80-'to-100° C.
aldehydes.
An object of this invention isethe provision of
reagent-formed couples with onemol of the an
phatic dihalogenpompound. This coupling re
or more,a cobalt salt catalyst, and ‘?nely-divided
relates more particularly to an-improyed :process
magnesium during the preparation of the Grig
for the production of bis-diacetals, whichmay'be
nard reagent, an intermediate coupling reaction
readily hydrolyzed to yield 'the corresponding _di— 5 may be favored whereby one mol of the Grignard
an efficient and economical process :for the
actionzresults'in the formation of aGrignardrea
preparation of bis-diacetals.
.gentwherein-the alkylene :group in ‘the chain is
Another object of this invention is the pro- 10 twice the length of the alkylene chain in the
.duction of aliphatic :dialdehydes from halogeninitialdihalogenated aliphatic compound. Mag
,ated vorganic compounds by converting said
‘nesium dihalide isobtained-as a by-product of
‘halogenated organic compounds to vbis-diapetals
the .couplingreaction. When theGrignard rea
followedby hydrolysiscf‘said'diacetals.
_ gent of increased alkylene chain length which
A further object of this invention is to-provide 1'0 is believed to beformed in'thisfashionis reacted
a process for the production of aliphatic dialdewith ethyl orthoformate, for example, the corre
hydes employing dihalogenated aliphatic com-'
wsponding longer chain aliphatic diethyl acetal is
pounds whereby the aliphatic 'dialdehydes obobtained. On hydrolysis, the latteris converted
tained may be of a longer chain lengththanthe
to the .longer chain dialdehyde. ‘By our improved
dihalogenated aliphatic compounds employed as 20 process, aliphatic dialdehydes of relatively high
intermediates.
~molecularweightmay be readily obtained.
Other objects of this invention-willzappear from
Thus, for example, when v'1,li-dichloro-lo-utane
the followingdetailed description.
isreacted with magnesium in a suitable solvent
Aside from glyoxal, the aliphatic ldialdehyde
to form .the Grignard reagent, 1,4-butylene-di
of lowest molecular weight, dialdchydes have :not 25 “magnesium-chloride is obtained as the primary
heretofore been readily available since methods
for their production directly and in suitable yield
have I101; been develeped- The bifunetional
character of dialdehydes, .whether ‘aliphatic, ali-
reaction product. "Under :favorable conditions,
1-chloro-octylene-8emagnesium-chloride is also
obtained as a secondary reaction product. 'The
"latter is ibelieved-to be formed by-reaction of a
cyclic or-aromatic, renders them of great value 39 part of the 1,4-butylene-di-magnesium-chloride
for use in many reactions, and methodswhereby
mwi-th unreacted lA-dichlcro-butane. 'The sec
Seid compounds may be obtained e?iciently and
economically andin highlyield are of considerable
commercial importance.
,ondary reaction product apparently undergoes
"furtherreaction with ‘the ‘magnesium in :the re
.action mixture'to-form the 1,8-octylenePdi-mag
‘We have new found that dieeetels "may be 35 nesium-chloride-Grignard reagent. Reaction of
readily obtained from the corresponding alpha,
omega-dihalogenated aliphatic compound or di-
the '1,4-butylene-di-magnesiumchloride‘and the
1,8-octylene-di-magnesium chloride Grignard
halogenated alicyclic or aromatic compounds by
reagents in the reaction mixture with ethyl or
converting the same to the Grignard reagent
thoformate yields adipaldehyde-bis-diethylacetal
employing magnesium and a suitable solvent un- 40 and sebacaldehyde-bis-diethylaceta1 respectively.
der anhydrous conditions, and then reacting the
Hydrolysis of said acetals under very mild acid
bifunctional Grignard reagent thus formed with
conditions results in the formation of free adip
an alkyl ester of orthoformic acid, such as, for
aldehyde and sebacaldehyde. The respective ace
example, ethyl orthoformate or methyl orthotals are preferably separated from each other by
formate to yield the corresponding aliphatic di- 45 fractionation prior‘ to hydrolysis to avoid subse
acetal. Examples of other esters of orthoformic
quent separation after hydrolysis.
acid which are suitable are propyl orthoformate,
The conditions under which the Grignard re
isopropyl orthoformate, butyl orthoformate, iso—
action ordinarily takes place are well known in
butyl orthoformate and isoamyl orthoformate.
the art. The Grignard reaction is, of course, a
Upon hydrolysis of the aliphatic diacetal, the de- 50 generic one and may be effected employing vari
sired aliphatic dialdehyde is obtained as the hyous halogenated aliphatic compounds such as, for
drolysis product. Furthermore, in the case of
example, chloro-, bromo- and iodo-compounds.
alpha,
omega-dihalogenated . aliphatic
com-
In the case of dihalogenated aliphatic compounds,
pounds, by maintaining rigidly anhydrous conthe alkylene group should contain at least four
ditions, employing adequate agitation, excess (11- 55 carbon atoms in the chain since with a lesser
2,572,948
-
3
The latter has a boiling point of 190 to 193° C. at
53 mm. pressure and an index ofrefraction of
number of carbon atoms, dehydrohalogenation
takes place forming unsaturates or ring com
pounds and not the desired Grignard reagent.
Thus, in addition to lA-dichloro-butane, 1,5-di
121325 1.4320.
dihalides such as 0-, m- or p-dichlorobenzene,
three hours. The reaction mixture is poured on
Example II
To 70 parts by weight of dry diethyl ether con
chloro-pentane, LB-dichloro-hexane, 1,7-dichl-o
' taining 12.5 parts by weight of magnesium turn
roheptane, l,8-dichloro-octane, etc. may be em
ployed. Other dihalogenated organic compounds
ings are slowly added 57.5 parts by weight of 1,5
which may be employed as intermediates in the
pentamethylene dibromide. ‘After all of the mag
preparation of said diacetals and dialdehydes are
nesium has been dissolved, 76 parts by Weight
alicyclic dihalides. such as cyclohexane dichloride‘ 10 of ethyl orthoformate are slowly added and the
and 1,4-dichloromethyl-cyclohexane, aromatic
reaction mixture heated under re?ux for about
1,4-di-(beta-chloroethyl) benzene. Diethyl ether ' to ice and the organic layer extracted with ether.
is normaly employed as the reaction solvent, al
The etherextract is dried, the ether evaporated
though other solvents may be employed to replace 15 and-the residue fractionated. Pimelic aldehyde
the ether in whole or in part. We have found that
bis-diethylacetal boiling at 100 to 110° C. at 0.3
methylal, dipropylformal, or even ethyl ortho
formate itself alone or in admixture with any one
mm._pressure is obtained.
The acetal may be
readily hydrolyzed to free pimelic dialdehyde un
or more of the solvents mentioned above may be
der mild acidic conditions.
20
conveniently employed as the reaction solvent.
It is to be understood that the foregoing
detailed description is given merely by way of
In order furtherrto illustrate our invention but
without being limited thereto, the following ex‘
illustration and that many variations may be
made therein without departing from the spirit
amples are given:
.
Example I
25
To a mixture of 560 parts by weight of diethyl
ether and 112 parts by weight of magnesium
shavings are added about 3 parts by weight of
ethyl bromide to initiate the desired Grignard
reaction and then 256 parts by weight of 1,4
‘Of our invention.
Having described our invention, what we de
sire to secure by Letters Patent is:
1. In a process for the production of bifunc
tional organic compounds, the steps which com
prise converting 1,4-dichlorobutane to the mag
nesium Grignard reagent at a temperature of
dichlorobutane are added with cooling while con
tinually stirring the reaction mixture. After the
about 80 to 100° C., reacting the magnesium Grig
nard reagent formed with ethyl orthoformate,
latter addition is complete 666 parts'by weight
and separating adipaldehyde - bis - diethylacetal
of ethyl orthoformate are added over about one
and sebacaldehyde-bis-diethylacetal from the re
half hour, 660 parts by weight of anhydrous ben
action mixture.
zene are added and the diethyl ether distilled
off, the mixture being maintained under re?ux at
65 to 70° C. for 4 hours. When the reaction is
completed, the reaction mixture is poured on to
crushed ice and the Grignard complex decom
posed. Magnesium hydroxy chloride is formed as
a by-product. The benzene solution is separated
and the water extracted with ether, if desired.
The benzene and the ether extracts are dried,
the benzene and ether distilled 01f and the re
maining product fractionated.
tional organic compounds, the steps which com~
prise converting 1,4-dichlorobutane to the mag
nesium Grignard reagent at a temperature of
about 80 to 100° 0., reacting the magnesium Grig
nard reagent formed with ethyl orthoformate,
separating adipaldehyde - bis - diethylacetal and
sebacaldehyde-bis-diethylacetal from the reac
tion mixture, and hydrolyzing said acetals to yield
the corresponding dialdehydes.
ALFRED L. MILLER.
Adipaldehyde
bis-diethylacetal is obtained in a yield of 35% of
theory. The latter has a boiling point of 186° C.
at 63 mm. pressure and the index of refraction
nD25 is 1.4215. Hydrolysis under mildly acidic 50
conditions, i. e. a pH of about ‘6, yields adipalde
hyde; Sabacaldehyde bis-diethylacetal is also
obtained in a yield of about 10% of theory al
though the reaction conditions employed are not
primarily chosen to favor the coupling reaction 55
Wherebyysaid longer chain compound is formed.
'
2. In a process for the production of bifunc
BERNARD H. KRESS.
REFERENCES CITED
The following references are of record in the
?le of this patent:
Post: “The Chemistry of Aliphatic Ortho
esters,” 1943, pages 96 to 105, Reinhold Publish
ing Corp.
-
.