Note: Descriptions are shown in the official language in which they were submitted.
Process for the Production of
Beta-hydroxypropionic acid amide
The present invention relates to a process for the
production of beta-hydroxypropionic acid amide ( ~-~PA) by
the conversion of acrylonitrile with water in the presence
of metals and/or metallic compounds that act. as catalysts.
Beta-hydroxypropionic acid amide has been described in
the literature for a considerable time: already familiar is
the reac~.ion of beta-propiolactone with ammonia to form
HPA (U5 Patent 2,375,005), the (carcinogenic) beta-
propiolactone being produced from ketene and formaldehyde.
Further, according to US Patent 2,415,645, ethylene
cyanohydrin can be converted to ~ -HPA by catalytic
saponification. The production of the ethylene cyanohydrin
~akes place by the conversion of ethylene oxide with
cyanide water.
A further possibility for producing beta-
hydroxypropionic acid amide starts with acrylonitrile. If
nitriles are saponified under basic conditions, this usually
results in the conventional salt.s of the corresponding
carbonic acids. During the hydrolysis of acrylonitrile with
an aqueous alkali solution one normally finds salts of the
acry~c or beta-hydroxypropionic acids as the reaction
products. (Journal of the Society of Chemical Industries of
Japan, 44, 860, (1941). lt is not simple to keep the
12383~1~
hydrolysis of the acrylonitrile at the stage of the amide,
since the rate of hydrolysis of the amide to the acid is
considerably higher than the rate of amide formation from
the nitrile.
Described herein is the hydrolysis of
acrylonitrile in the presence of water and heterogenous
catalysts to form acrylamide as the reaction product. As an
example, metallic copper together with copper(I)- and/or
copper(II) salts (US Patent 3,3~1,034), activated MnO2
(German Patent 15 93 320), reduced CuO or reduced copper-
chromium oxide (DE-OS 20 01 903) or Raney-copper or other
metallic catalysts (DE-OS 20 36 126) are used as catalysts.
Thus, although it is known that acrylamide can be produced
by the conversion of acrylonitrile with water in the
presence of metallic catalysts such a Raney-copper, Ullmann
copper, other Raney metals or copper catalysts that contain
additional metallic oxides, it is not, however, possible to
apply these hydration reactions, which must proceed under
neutral conditions,to the acrylamide for the production of
beta-hydroxypropionic acid amide.
A controlled conversion of acrylonitrile to ~ -HPA is
described in US PS 3 670 020. Alkali or earth alkali
metallic hydroxides as well as organic substances such as
tertiary or quaternary onium hydroxide and onium salts are
cit.ed as catalysts for the basis hydrolysis. In order to
~38~
obtain the greatest possible yield of ~-HPA in the process
described,a pressure of greater than 20 bar is required.
With the use of NaOH as a catalyst,with an increased yield of
~ -HPA one observes increased production of be~a-
hydroxypropionic acid. ~owever, the occurence of beta-
hydroxypropionic acid as a by-product hinders the
crystallisation of ~-HPA, so that simple processing of the
reaction product is rendered more difficult. For this
reason, what is sought is a simple process for the
production of ~ -HPA from acrylonitrile, which provides high
yields of ~-~PA at relatively low pressure, without the
formation of undesirable beta-hydroxypropionic acid.
Most surprisingly, it has been found that acrylonitrile
can be converted to ~ -HPA in high yields if carried out at
a temperature higher than room temperature up to 200 C in the
presence of metals and/or metallic compounds as catalysts,
preferably Raney metals and/or metallic compounds thereof
in a narrowly defined pH range, namely 11.8 - 13.5, with
water, preferably desalinated, whereby no--or only
small quantities of--beta-hydroxypropionic acid is formed
as a by-product.
The object of the present invention is a process for
the production of beta-hydroxypropionic acid amide by the
conversion of acrylonitrile with water in the presence of
metals and/or metallic compounds as heterogenous catalysts,
12383a~
characterized in that the reaction is carried out at pH values
from 11.8 - 13.5, and at temperatures between 20C and
200C.
Conversion at p~ values of 12.8 - 13.2 is preferred.
The reaction temperature is preferably in a range from 70 -
200, especially 90 - 170C.
It is preferred that Raney metals be used as the
catalysts. The Raney metal can be Raney copper, Raney
nickel, or Raney cobalt. In place of the Raney metal or in
addition to the Raney metal it is possible to use metallic
compounds, preferably of the above-quoted Raney metals.
Suitable metallic compounds are the oxides and hydroxides
as well as the salts of the Raney metals. Suitable metallic
compounds are, for example, copper(II) oxide or cobalt(llI)
oxide or copper (II) salts such as basic copper carbonate,
copper oxychloride, copper sulfate, or copper nitrate or
cobalt compounds such as Co(0~)2.
The reaction can be carried out both in the presence of a
Raney metal or in the presence of one of the quoted metallic
compounds and in the presence of a combination of Raney
metal and metallic compound. ln the latter case, the
quantities used are adju~ted to the quantity ratios that
apply to the individual components. The reaction components
are to be freed of oxygen before the reaction, for the
:~3~ 4
presence of oxygen contributes to the formation of
undesirable beta-hydroxypropionic acid and an increased
formation of metal ions in the product.
The weight ratio of Raney metal to acrylonitrile
amounts, preferably, to 0.01 to 2, preferably 0.1 to 1Ø The
weight ratio of metallic compound to acrylonitrile is
preferably 1.0 to 0.0005. In the process according to the
present invention the reaction components are heated while
being stirred, in a reactor, to a reaction temperature
between 20OC and 200C, preferably higher than 70C,
particularly to 90 - 170C . At temperatures above 100C
the reaction is carried out in a pressure-resistant reactor,
in which a pressure of 1 - 10 bar is generated. The
conversion is not particularly affected by pressure.
The weight ratio of acrylonitrile to water is varied
between 0.01 to 1.47, preferably from 0.10 to 0.74.
In order to increase the speed of hydration of the
acrylonitrile a nitrate compound, for example, aluminum
nitrate, can be added as an activator, in which regard the
period of use of the metallic catalyst is retainedfor longer
periods. 1'he quantity of nitrate ions amounts preferably to
1 - 600 ppm, calculated as the weight ratio of the nitrate
ion to the gross weight of the mixture of acrylonitrile and
water.
The desired pH value is adjust.ed by the addition of a
base .
~2;:~839~
Alkali metal hydroxides, for example, lithium
hydroxide, sodium hydroxide or potassium hydroxide, or
quarternary ammonium hydroxide, for example,
trimethylbenzyl ammonium hydroxide can be used as the base.
The quantity of base is so selected that the pH value of
the solution is between 11.8 and 13.5, preferably between
12.8 and 13.2.
After a reaction time of 5 minut.es to 24 hours the
product can be processed. The processing can include
filtration, cation exchanae and anion exchange stages, and
subsequent ~emoval of the volatile residue by distillation
which should take place at a reduced pressure at temperatures
below 130C.
The beta-hydroxypropionic amide can be extracted by
crystallisation from the water-free product so obtained,
whereby a temperature below O C is an advantage. The
product can be further purified by recrystallisation from
short-chain aliphatic ketones, for example, acetone or
methylethyl ketone.
The catalyst that is used according to the present
invention, consisting of Raney metal and metallic oxide, can
be reused several times without any noteworth reduction in
the activity of the catalyst.
The ~ -HPA produced according to the present invention
can be used as a starting materialfor the production of
~3~1~4~
alpha-beta unsaturated substituted carbonic acid amides
according to ~S Patent 4,237,067 or US Patent 4,408,073
which, in turn, can be pol~nerized to high-molecular
flocculating agents.
Further to this, the ~-HPA can be used as a starting
material for the production of ester amides and polyester
àmides and as an intermediate product in the production of
pharmaceuticals, insecticides and pesticides. It can also
be used as a thermal storage medium for heat pumps.
Example 1:
500 g desalinated water, 2 g NaOEl, 75 mg Al(NO3)3,9 ~2,
100 mg hydroquinone as well as 70 g acrylonitrile were placed
in a pressure-resistant stainless steel 2-1 reactor fitted
with a pressure gauge, oil bath heater and stirrer, and
~leansed of dissolved oxygen with nitrogen. 25 g Raney
copper were washed with oxygen-free water and placed in the
reactor with 6 g copper oxide powder. The pH value of the
mixture amounted to 12.9. The mixture was heated to 150C,
this generating a pressure of approximately 6 bar. l'he
reaction time amounted to 3 hours. A clear, green liquid
was obtained as the product of the reaction. I'he raw
product was passed over a cation exchanger in order to
remove the copper ions and subsequently freed of volatile
residues in a vacuum at 100C and 0.5 mbar. The viscous,
12~ 4
brown product was analysed by means of HPLC; it consisted of
72%-wt beta-hydroxypropionic amide and 24~-wt ethylene
cyanohydrin.
Example 2:
The process used in Example 1 was repeated, the quantity of
acrylonitrile used amounting to 96 g. The pH value of the
mixture was 12.8. The reaction time amounted to 4 hours at
a temperature of lSOoC and at a pressure of approximately 6
bar. A light-green, clear liquid was obtained as the
reaction product. After the removal of the copper ions by
means of a cation exchanger the raw product was freed of
volatile residues at 100C and at 0,5 mbar. Analysis of the
viscous, brown product indicated 70%-wt beta-
hydroxypropionic amide and 28%-wt ethylene cyanohydrin.
Examples 3 - 6:
In these tests the catalyst system, consisting of Raney
copper and copper oxide as in Example 2, was used once again. 500
g H20, 2 g NaOH, 100 mg Al(N03)~.9 H20, 100 mg hydroquinone and
70 g acrylonitrile were added to the reactor with the Raney
copper and the copper oxide already therein, oxygen being
excluded. The pH value of the solution amounted to 12.9 to
13Ø At 150C the pressure amounted to approximately 6 bar and
the reaction times amounted to 6 hours. Light-green liquids were
obtained as reaction products. The raw products were treated
wit.h a cation exchanger and freed of volatile residual fractions
at lUOoc and 0.5 mbar.
12~33~4
The results of analysis are set out in the following table:
Example % HOCH2CH2CONH2 ~ HOCH2CH2CN HOCH2CH2COOH
3 7028
4 5422
5121
6 5837 trace
. _
Examples 7 - 12:
In these tests, the catalyst system was varied, otherwise
the same procedure as in Example 1 was followed. KOH and LioH
were used in place of NaOH, and in place of Raney copper, Raney
cobalt or Raney nickel were used; CuO was replaced by Co203 The
pH values of the mixtures were between 12.4 and 13.1. The
results are set out in the following Table 1:
~ HCH2CH2-~ OC 2CH2 HOCH2 2
Example Catalyst CONH2 COOH
.
7 Raney-Cu/CuO/NaOH 65,5 31,5
8 Raney-Cu/CuO/KOH 47,4 ca. 30
9 Raney-Cu/CuO/LiOH 44,2 10,8
Raney-Co/CuO/NaOH 52,8 3,9 little
11 Raney-co/co2o3/NaoH48,4 ca. 20
12 Raney-Ni/CuO/NaOH 53 ca. 10
~2~8344
Example 13:
As in Example 1, 810 g desalinated water, 0.5 g ~aOH, 100 mg
Al(NO3)3 . 9 ~2' 100 mg hydroquinone and 159 g acrylonitrile
were mixed in the presence of 8U g Raney copper. The mixture had
a pH of 12Ø After a reaction time of 4 hours at a
temperature of 15UC and at a pressure of approximately 6 bar, a
clear brown liquid was obtained. The raw product was freed of
volatile residual fractions in a vacuum at 100OC and 0.5 mbar.
The viscous brown product consisted of 39.4% beta
hydroxypropionic amide and 17.1~ ethylene cyanohydrin~
Example 14:
As in Example 1, 432 g desalinated water, 5 g NaOH, 500 mg
Al(N03~3 . 9 H20~ 100 mg hydro~uinone and 159 g acrylonitrile
were added to 80 g Raney copper. The mixture had a pH value of
13.4. After 4 hours reaction time at a temperature of 150C at a
pressure of approximately 7 bar a brown liquid was obtained.
After conventional processing, the product was analysed. It
contained 46.5% beta-hydroxypropionic amide and 9.7% ethylene
cyanohydrin
Examples 15 - 22:
As in the process described in Example 1, in tests 15 -
22, in each instance, 810 g desalinated water, 100 mg
Al(NO3)3. 9 H2O, 100 mg hydroquinone 159 g acrylonitrile,
and the quantities, set out in Table 2, of sodium hydroxide
and metallic compounds were brought to react.ion. After
49~
conventional processing, the quantities of ~-HPA in the
products weredetermined, and these quantities are set out in
Table 2.
Table 2
Example Catalyst Quantity NaOH pH %~-HPA ~ ECH
(g) (g)
CU(NO3)2.3H2020 8 12,4 28 17
16 CuCl2.3Cu(OH)220 8 13,1 39 24
17 CU(OH)2 CUCO340 5 12,8 50 4
18 4 2 20 7 12,2 41 21
19 CUSo4 5H2 20 9 12,7 32 20
CuO , 20 5 12,8 46 5
21 CuO 60 5 12,8 53 16
22 Co(OH)2 20 5 13,0 42 41
Example 23:
In accordance with the process described in Example 1, 810 g
desalinated water, 100 mg Al(~03)3 . 9 H2O, lOO mg hydroquinone
159 g acrylonitrile, 5 g sodium hydroxide, and 80 g Raney copper
that had been washed with water, were mixed together. The
reaction time amounted to 4 hours at a temperature of 150C and a
pressure of 40 bar. After conventional processing analysis
indicated 63~ ~-HP~ and 18~ ECH.
12~ 4~
Example 24:
According to the process described in Example 1, 360 g
desalinated water, 80 mg Al(N03)3 . 9 ~2~ 100 mg hydroquinone
265 g acrylonitrile, 1 g sodium hydroxide, and 50g ~aney copper
that had been washed with water and 0.4 g copper oxide were mixed
together. The reaction time amounted to 6 hours at a temperature
of 150C and a pressure of approximately 6 bar. After
conventional processing analysis of the product indicated 22
~-HPA and 24% ECH.
Example 25:
According to the process described in Example 1, 500 q
desalinated water, 100 mg Al(N03)3 . 9 H20, 100 mg hydroquinone
70 g acrylonitrile, 50 g Raney copper and 5 g copper oxide were
mixed together. The adjustment of the pH 12.4 was
effected by the addition of 8 g benzyltrimethyl ammonium
hydroxide (40% solution in water). The mixture was brought to
reaction at 150C at a pressure of approximately 6 bar for 5
hours. After conventional processing of the product, analysis
revealed 48~ ~-HPA and 20~ EC~l.
Example 26:
According to the process described in Example 1, 500 g
desalinated water, 300 mg Al(N03)3 . 9 H20, 100 mg hydroquinone
1.5 g NaOH and 100 g Raney copper washed with water were
brought to reaction. The reaction temperature of 170C, at which
a pressure of approximately 9 bar was generated, was maintained
for a period of 15 minutes. After conventional processing of the
1~
~2~ 44
product, analysis revealed 5~% ~-HPA and 11% ECH.
Example 27:
500 g desalinated water, 300 mg Al(N03)3 . 9 H20, 100 mg
hydroquinone 1.5 g NaOH and 100 g Raney copper washed with water
as well as 100 g acrylonitrile were placed in an open glass
vessel with a reflux cooler and stirrer. The mixt~re was kept at
a temperature of 90C for 3 hours whilst being stirred
constantly. After conventional processing of the product,
analysis revealed 35% ~-HPA and 20% E~H.
Example 28-
According to the process described in Example 1, 960 gdesalinated water, 100 mg hydro~uinone 100 g acrylonitrile,
3 g NaOH and 100 g Raney copper washed with water were mixed
together. The mixture had a pH value of 12.8. The reaction
time amounted to 3 hours at a temperature of 140C at a
pressure of approximately 5 bar. After conventional
processing, analysis revealed 72~ -HPA and 11% ECH.
Example 29:
According to the process described in Example 1, 810 g
desalinated water, 100 mg Al(~03)3 . 9 H20, 100 mg hydroquinone
159 g acrylonitrile, 3 g NaO~ and 80 g Raney copper washed with
water with 0.1 g copper oxide were mixed together. The mixture
had a pH of 12.8. The reaction time amounted to 24 hours
at a temperature of 150C at a pressure of approximately 6 bar.
After conventional processing, analysis revealed 57% ~-HPA and
29% ECH.
Comparative Example (as in US Patent 3,670,020)
In this example, neither Raney copper nor metallic
oxide were used. As in Example 1, a mixture consisting of
810 g H2O~ 14 g NaOH, 100 mg hydro~uinone and 159.2 g
acrylonitrile was brought to reaction. The mixture had a pH
of 13.5. After conventional processing, analysis of
the product indicated 27.4% beta-hydroxypropionic amide,
12.1% ethylene cyanohydrin, approximately 35%
hydroxypropionic acid.
Comparative Example (as in DE-O~ 20 36 126)
.
In this example, the process followed tha~ described in
Example 1, however, no NaOH was used. The mixture had a pH
of 9.6. Analysis of the product, processed as is usual,
indicated 10.5~ beta-hydroxypropionic amide, 4.3% ethylene
cyanohydrin, main component, acrylamide~
