PRODUCTION OF UNSATURATED CARBONYL COMPOUNDS

PRODUCTION DE COMPOSES CARBONYLES NON SATURES

English Abstract

ABSTRACT
To produce an unsaturated carbonyl compound, a
carbonyl compound is contained with an aluminum oxycarbonate
catalyst, the water formed by the reaction being removed as it
is formed. Thus, for example, trimethylnonenone can be produced
from methyl isobutyl ketone, mesityl oxide from acetone, cyclo-
hexylidene cyclohexanone from cyclohexanone, and phenyl beta-
methylstyryl ketone from acetophenone.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A process for producing an unsaturated carbonyl
compound, which comprises contacting at least one ketone or
aldehyde with an aluminum oxycarbonate catalyst, the water
formed by the reaction being removed as it is formed.
2. A process according to claim 1 wherein the ketone
or aldehyde or at least one of the ketones or aldehydes has
the general formula:
<IMG>
wherein R1 and R2 are the same or different and each is a
hydrogen atom, an alkyl group, a cycloalkyl group, an aryl
group, an alkaryl group or an aralkyl group, or R1 and R2
together form an alkylene group.
3. A process according to claim 2, wherein methyl iso-
butyl ketone is contacted with the catalyst to produce trimethyl-
nonenone.
4. A process according to claim 2, wherein acetone is
contacted with the catalyst to produce mesityl oxide.
5. A process according to claim 2, wherein cyclohexanone
is contacted with the catalyst to produce cyclohexylidene
cyclohexanone.
6. A process according to claim 2, wherein acetophenone
is contacted with the catalyst to produce phenyl beta-methyl-
styryl ketone.
7. A process according to claim 2, wherein an alpha-
beta unsaturated ketone or aldehyde or a mixture thereof with a
different ketone or aldehyde, is contacted with the catalyst.
8. A process according to claim 7, wherein mesityl
oxide is contacted with the catalyst to produce a C9-di-
unsaturated ketone.
9. A process according to claim 1, 2 or 3, wherein the

reaction is carried out in the presence of a solvent to aid
in the removal of water.
10. A process according to claim 4, 5 or 6, wherein the
reaction is carried out in the presence of a solvent to aid in
the removal of water.
11. A process according to claim 7 or 8, wherein the
reaction is carried out in the presence of a solvent to aid
in the removal of water.
12. A process according to claims 1, 2 or 3, wherein the
catalyst is in the form of a fixed bed or a fluidised bed.
13. A process according to claims 4, 5 or 6, wherein the
catalyst is in the form of a fixed bed or a fluidised bed.
14. A process according to claims 7 or 8, wherein the
catalyst is in the form of a fixed bed or a fluidised bed.
15. A process according to claims 1, 2 or 3, wherein the
process is effected at a temperature of from 80 to 150°C.
16. A process according to claims 4, 5 or 6, wherein the
process is effected at a temperature of from 80 to 150°C.
17. A process according to claims 7 or 8 wherein the
process is effected at a temperature of from 80 to 150°C.
18. A process according to claims 1, 2 or 3, wherein the
activity of the catalyst is maintained and/or enhanced by
treating it with CO2.
19. A process according to claims 4, 5 or 6, wherein the
activity of the catalyst is maintained and/or enhanced by
treating it with CO2.
20. A process according to claims 7 or 8, wherein the
activity of the catalyst is maintained and/or enhanced by
treating it with CO2.

Description

PRODUCTION OF UNS~TURI~TF,D CARBONYL COMPOUNDS
_ _ _
This invention relates to the use of an aluminum
oxycarbonate catalyst in the production of unsaturated carbonyl
compounds with simultaneous removal of water of reaction to
maintain the catalytic activity of the oxycarbonate catalyst.
According to the invention, there is provided a
process for producing an unsaturated carbonyl compound, which
comprises contacting at least one ketone or aldehyde with
an aluminum oxycarbonate catalyst, the water formed by the
reaction being removed as it is formed.
The invention can be used, for example, in an aldol
condensation and dehydration process for increasing the
molecular weight of carbonyl compounds. The catalyst com-
monly used for such a process is sodium hydroxide. This
process generally yields hydroxy carbonyl compounds which are
often dehydrated to form unsaturated carbonyl compounds in the
presence of an acid catalyst. For example, acetone is con-
densed in the presence of an alkaline compound to yièld di-
~acetone alcohol which is then dehydrated to yield mesityl
oxide.
In accordance with the prese~t invention, the aldol
condensation and dehydration process can be carried out using
-an aluminum oxycarbonate catalyst in either a fixed or in a
~luidised bed. Degradation of the aluminum oxycarbonate
-~atalyst can be avoided, when the reaction is stopped, by
the application of C02 to the catalyst.
As used herein, the term "aldol condensation" means a
.

4~9
--2--
combined condensation-and-dehydration reaction utilizing
carbonyl compounds (i.e. aldehydes and/or ketones), the
term "fixed bed" means a stationary catalyst bed through
which vapours and liquids move, and the term "fluidised
bed" means a suspension of catalyst particles, the suspen-
sion being maintained by agitation.
The aldol condensation produces alpha-beta unsaturated
carbonyl compounds. The aluminium oxycarbonate catalyst,
maintained in either a fixed or fluidised bed, is also useful
in the substitution of other carbonyl groups into such
alpha-beta unsaturated carbonyl compounds. The substitution
- oeeurs at the alpha earbon of the unsaturated earbonyl
eompound. Water of reaetion may be removed direetly or it
may be removed by reversal of the aldol eondensation reaetion.
The proeess of the present invention ean be used to
eondense a wide variety of aldehydes and ketones. Carbonyl
compounds containing from two to twenty carbon atoms are
particularly desirable for condensation, but higher molecular
weight carbonyl eompounds ean be used.
By the proeess of the present invention, it is now
possible to eondense higher moleeular weight ketones.
If only one earbonyl eompound is used in the aldol
eondensation proeess aeeording to the present invention, it
preferably has the following general formula:
.-

HCH ~ C - R1 (i) -
R2
30 wherein R1 and R2 are the same or different and eaeh is a .
hydrogen atom, an alkyl group, a eyeloalkyl group, an aryl
group, an alkaryl group or an aralkyl group, or R1 and R2 '
together form an alkylene group.
If two distinet aldehydes and/or ketones are used, at '~
least one of them preferably has the general Formula (I).
The aluminium oxyearbonate catalyst ean be prepared
by heating aluminium hydroxide in a earbon dioxide atmosph-
ere. The eatalyst may also be prepared by heating A1203

4~39
"
--3--
in a CO2 atmosphere, or by treating aluminium oxide
or hydroxide with CO2, while the aluminium compound is
wetted with water or with a carbonyl compound. Other
methods of combining aluminiurn with carbon dioxide will be
apparent to those skilled in the art.
The catalytic activity of the aluminium compound
improves rapidly with the initial addition of CO2 but soon
reaches a very efficient state that improves little
thereafter. The ratio of Al:CO2:O can vary widely. Some
CO2 is essential to ensure the catalytic activity of the
catalyst.
The aluminium oxycarbonate catalyst may be used in
various forms, for example as granules, pellets or powders.
In the process of the invention, the catalyst is preferably
maintained in a suitable reaction tube or chamber. The
catalyst may be employed in a fixed bed over which the
carbonyl compound in vapour and/or liquid form may be
passed ~hile carrying out the aldol condensation reaction.
The catalyst may also be employed as a fluidised bed.
The temperature at which the aldol condensation reaction
is carried out can be up to 200C or higher. The preferred
temperature range is between 80C and 150C. The reaction
speed decreases with temperature. At higher temperatures
more undesired side reactions occur. The aldol condensation
reaction should be conducted at a temperature at which the
reactant and product remain stable. For example, aldehyde
begins to decompose at about 250 C.
The pressure at which the aldol condensation reaction
is carried out may be, for example, from sub-atmospheric
to about 50 atmospheres. The preferred pressure range is
between 1 and lD atmospheres. During the reaction, the
carbonyl compound may be in the vapour phase and/or the
liquid phase, but preferably it is a mixture of vapour and
liquid with the vapour and liquid components of the mixture
moving in opposite directions through the bed of the catalyst. ;
The preferred reaction conditions are such that the
water of reaction is azeotropically removed from the catalyst
chamber. Removal of water is essential to maintain the
required catalytic activity of the catalyst. When using
.
t

_4_
carbonyl ccmpounds th~t readily ,.orn an azeotrope with water, it is
convenient to operate at atm~spheric pressure and at a temperature at
or near the normal boilding point of the carbonyl ~ ~ound. When using
compcunds such as acetone which do not readily form ~n azeotrope with
water at such pressure and temperature, then the pressure and temperature
may be raised. A solvent can be added to aid in the formation of an
azeotrope and in separating the water.
Under the preferred reaction conditions, the hot vapours
moving up through the catalyst bed contain the water of reaction,
10 Upon condensation, the water separates from the organic condensate. ;:
The organic condensate is refluxed through the catalyst thereby
removing the reaction product. Rem~val of the product from the catalyst
bed is desirable to minimize formation of undesirable by-products.
Keeping the catalyst wetted ~ith the liquid reactant also suppresses ~
15 the iormation of such by-products. ;~,
When using a fluidised bed, it is preferred to
remove the reaction mixture solution at reaction product concentrations
of 75% or less, to limit the formation of such by-products.
In general, pressures of 1 to 10 atmospheres are
preferred to e~tablish the boil ing points of the carbonyl
compounds in the desired 80C to 150C temperature operating
range. ~s
In the presence of the aluminium oxycarbonate cat-
alyst, the aldol condensation dehydration process is rever-
25 sible, which is an important advantage of the invention. Due
to this reversibility of the aldol condensation process, it
is now possible to produce additional unsaturated carbonyl
compounds by contacting the aluminium oxycarbonate catalyst
with alpha-beta unsaturated carbonyl cQmpounds, either
30 a~one or in the presence of another carbonyl compound. The
reaction conditions previously described can be used to
produce these additional compounds but temperatures below ~i
80C can also be used. 3
The present invention will be illustrated by the 'i
35 ~ollowing Example~. s
Example 1 lj
There was used an aldol condensation dehydration ~
pilot plant consisting of (1) an autoclave ~itted with heating

0~
--5--
steam coils, (2) a 15 cm diameter vertical tube having a
"catalyst chamber" extending above the autoclave, sections
of this tube above and below -the catalyst chamber being
packed with ceramic saddles, 1(3) a condenser, and (4) a
condensate receiver.
Methyl isobutyl ketone (MIBK) was refluxed in the
autoclave at atmospheric pressure. The 2,6,8-trimethyl-5-
nonen-4-one (TMN0) formed was removed from the bottom of
the autoclave. The catalyst chamber was packed with the
aluminium oxycarbonate catalyst.
The water by-product from the reaction was removed
from the receiver while the MIBK from the receiver was
returned to the top of the vertical tube as reflux.
The operating conditions were as given in the following
Table 1:
Table 1
Catalyst DepthRun Time TMN0 ~ate TMN0
(cm) (Hours) (kg) (gm/~cm2/hr#) (%)
24 11 9 4.4 100
81 260 9?7 20 98
*Gram23085 80.5 536 `;46 96.6
jcm2 of cros s sectional area of e catalyst ch ~mber
- Example 2
The plant described in Example 1 was used. Acetone
was refluxed through the catalyst bed while mesityl oxide
was removed from the autoclave. Normal pentane was refluxed
to the top of the tube to aid in the removal of water from
the refluxing acetone. Water was removed from the receiver.
- The operating conditions were as given in the following
Table 2:

?4,~9
--6--
Catalyst Depth Plessure Conversion Rate
(cm) (Atmos~heres) (gm/cm2/hr)
142 3 3.7 - 5.4 ;
142 3.7 4.4 - 7.3
142 4~4 6~3
142 5.1 7.8 - 9.3
142 - 5.8 11
142 6.4 14.6 - 16
10 305 7.8 49
Example 3
There was used a plant as described in Example 1 with --
a catalyst depth of 305 cm. The plant was pressurised
15 overnight with CO2 at 3.7 atmospheres. This CO2 treatment
enhanced the catalytic activity of the aluminium oxycarbonate
and the conversion rate to TMNO increased to more than 50
gm/cm /hr.
Example 4
A three litre flask equipped with a stirrer to produce
a fluidised bed was used. A receiver and condenser extended
upward from the flask. To the flask, 1 kg of MIBK and 100 ~
gm of aluminium oxycarbonate (fine powder) were added, and '
heated to an initial boiling point of 115C. The MIBE and
25 water formed an azeotrope, and 67 ml of MIBK saturated with
~ater was removed. Thereafter, MIBK was continually refluxed
to the flask. Over a ten hour period, the temperature of
the flask increased from ll5C to 145C, and 760 gm of -~
product were removed from the reaction flask. Distillation
30 produced 250 gm of MIBK and 410 gm of TMNO. Remaining from
the distillation was 100 gm of residue. The conversion of
MIBK was 70%. The reaction product was 80.4% TMNO.
This Example illustrates that the aluminium oxycarbonate ~
- catalyst can be utilized in a fluidised bed as well as in a ~,
35 fixed bed. -
Example 5
A three litre flask was used to carry out an aldol
condensation process. Extending from the flask was a 50 mm
diameter column. The column was packed at the bottom with
.. . . . ... . _ . . . _ _ . ..

1~(3~
--7--
ceramic saddles. The centre 25 cm section of the column was
packed with aluminium oxycarbonate. The top 12 cm section
of the column was packed with ceramic or porcelain saddles.
A receiver and a water-cooled condenser were operatively
5 coupled to the top section of the column. -
The flask was charged with 1,800 ml of methyl ethyl
ketone (MEK) and refluxed at atmospheric pressure. A small
amount of n-hexane, added to the condenser, aided in the
water separation. After refluxing for 13 hours, approximately
lO 70% of the original MEK was condensed to a product having
a distinct spicy odor. The condensation products were
5-methyl-4-hepten-3-one and 3,4-dimethyl-3-hexen-2-one.
Example 6
The same equipment as described in Example 5 was used.
15 The flask was charged with:1,600 ml of n-butanal and 200 ml
of n-hexane. Refluxing at atmospheric pressure, the
n-butanal was condensed to 2-ethylhexenal at a rate of approx-
imately 20 gm/hr.
Example 7
The same equipment as described in Example 5 was used.
The flask was charged with 2,500 ml of mesityl oxide.
Refluxing at atmospheric pressure resulted in a mixture of
Cg di-unsaturated ketones. The conversion rate was approx-
imately 300 gm/hr. Removal of water was accomplished by ~
25 revérsal of the aldol condensation reaction to form acetone. .~
The acetone was removed from the reaction while it was being
formed.
Example 8 'c
The equipment of Example 1 was used. The catalyst
30 had a depth of 24 cm. It was allowed to stand overnight.
The reaction was restarted tkenext day. The rate of formation
of TMNO was slightly greater than 3.9 gm/cm /hr. After '
standing again overnight, the rate of TMN0 formation was less
than that amount. Loss of activity of the catalyst continued
35 with subsequent stops and starts. To prevent such degradation
of the catalyst, C02 treatment of the catalyst at each shut-
down was used. After such CO2 treatment, no apparent loss
of catalytic activity reoccurred.
,;

--8--
Example ~
TMNO was heated in the presence of alnminium oxycar-
bonate using the same equipment as described in Example 4. r
The resulting products were decanted and distilled. The
5 distillate consisted of MIBK, unreacted TMN0, C
di-unsaturated ketones, and distillation residues.
Example 10 Xs
Using the equipment as described in Example 4, 1500
ml of cyclohexanone and 100 gm of aluminium oxycarbonate
lO were added to the flask, and heated to an initial boiling -'
point of 142C. Water evolved quickly and the temperature `
of the flask rose to 200C in three hours. The liquid
was decanted, and distilled to yield unreacted cyclohexanone,
cyclohexylidene cyclohexanone, and a higher molecular
15 weight condensation product, C18H26O, believed to be
di-cyclohexylidene cyclohexanone.
Example 11
Using the equipment as described in Example 5, 1500 ml
of cyclohexanone were added to the flask, and heated to
2g boiling. After seven hours the temperature of the flask
was 210C. Distillation yielded about 80% cyclohexylidene
cyclohexanone together with unreacted cyclohexanone. Very
little of the higher molecular weight condensation products
were produced.
25 Ex~mple 12
Using the equipment as described in Example 4, 1700
ml of acetophenone were added along with 300 gm of the
catalyst. Also added, as a solvent, were 100 ml of hexane
to suppress the-boiling point and to form an azeotrope with the
30 water. The aldol condensation was rapid. The yield was
65% phenyl beta-methylstyryl ketone. ~-
As will be apparent to those skilled in~the art, the ~-
invention provides a process which can be very efficient and
economical~. Simplicity of the process and the required
35 equipment make it possible to utilize small and, therefore,
relatively inexpensive production plants. Accordingly, ~~
these smaller plants can be more advantageously located
near the source of materials or markets. In addition, the
process of the invention can produce products for which no
previously known process was commercially suitable.
.