Cyanobutylation of ammonia, alkylamines and hydrazine with 3-pentenenitrile, 4-pentenenitrile or mixtures thereof

The present invention relates to a process for the cyanobutylation of ammonia, an alkylamine or hydrazine with 3- and 4-pentenenitrile and mixtures thereof to form alkylaminonitriles.

The present invention relates to a process for the cyanobutylation of 
ammonia, primary and secondary alkylamines and hydrazine with 3- and 
4-pentenenitrile and mixtures thereof to form alkylaminonitriles. The 
aminonitriles or alkylaminonitriles formed by the process of the present 
invention can be hydrogenated to form alkyldiamines. 
BACKGROUND OF THE INVENTION 
U.S. Pat. Nos. 4,260,556 and 4,211,725 teach reaction of 2-pentenenitrile 
with ammonia or ethylenediamine to produce alkylaminonitriles. U.S. Pat. 
No. 4,496,474 teaches the reaction of 2-pentenenitrile with alkylamines 
having from 8 to 22 carbons to produce the corresponding nitrile compound. 
U.S. Pat. No. 5,070,202 teaches a process having improved reaction rate 
and selectivity in the reaction of 2-pentenenitrile with amines to form 
alkylaminonitriles by the incorporation of from 15 to 60 weight percent 
water in the reaction mixture. 
It has now been found that alkylaminonitriles can be made with high yields 
and selectivities using 3-pentenenitrile, 4-pentenenitrile and mixtures of 
these isomers. 
SUMMARY OF THE INVENTION 
The present invention is a process for making aliphatic aminonitriles 
comprising the steps of forming a reaction mixture comprising 
3-pentenenitrile, 4-pentenenitrile or mixtures of 3-pentenenitrile and 
4-pentenenitrile and ammonia, an alkylamine or hydrazine, or optionally 
forming the reaction mixture in the presence of water or incorporating 
water into the reaction mixture; and reacting the mixture at a temperature 
from about 25 to 200.degree. C. and at pressures from autogeneous to 
pressures of about 1500 psig. 1500 psig. 
The reaction rate of the process may be increased by the addition of a 
strong base such as a water soluble alkali metal hydroxide, an alkaline 
earth metal hydroxide, a tertiary amine, for example, 
1,3-di-methylpiperidine, triethylamine and pyridine, a Lewis base, a 
strongly basic ion exchange resin, a basic alumina or zeolite. 
The present process may also be carried out with a solvent present in the 
reaction mixture. The solvent may be used alone or in combination with 
water. The preferred concentration of water in the reaction mixture is 
from 15 to 60% by weight. 
The weight ratio of 3-pentenenitrile to 4-pentenenitrile in the present 
process may be from 0 to 1 to 1 to 0. 
The present process may be run as a continuous or a batch process. 
DETAILED DESCRIPTION 
The present invention is a process for making aliphatic aminonitriles 
comprising the steps of forming a reaction mixture comprising 
3-pentenenitrile, 4-pentenenitrile or mixtures of 3-pentenenitrile and 
4-pentenenitrile and ammonia, an alkylamine or hydrazine, or optionally 
forming the reaction mixture in the presence of water or incorporating 
water into the reaction mixture; and reacting the mixture at a temperature 
from about 25 to 200.degree. C. 
The present process is suited for cyanobutylation of both primary and 
secondary amines, and accordingly as used herein the term alkylamine 
includes both primary and secondary amines. 
Aminonitriles formed in the present process from the reaction of the 
subject pentenenitriles with ammonia, alklyamines or hydrazine are useful 
as starting materials for making various polymer classes. For example, the 
product aminonitrile formed when ammonia or hydrazine is reacted with the 
subject pentenenitriles according to the present process may be 
hydrogenated to form 1,3-pentanediamine. 1,3-pentanenediamine has a 
variety of uses such as use a monomer for forming polymers including 
polyamides, polyimides and polyurethanes-polyureas. 1,3-pentanediamine may 
be used as a chain extender, a metal chelating agent or as an epoxy curing 
agent. 
To form the diamine from the animonitrile products of the present 
invention, the amoninitrile is usually hydrogenated. Typically such 
hydrogenations are carried out over metal catalysts such as RANEY nickel, 
RANEY cobalt, RANEY nickel or RANEY cobalt catalysts promoted with 
chromium, nickel, iron, molybdenum or mixtures of any of these metals 
(RANEY is a trademark of W. R. Grace and Company), supported nickel or 
cobalt catalysts, palladium, platinum, ruthenium or iron catalysts. The 
hydrogenation is typically run at temperatures of from about 75 to 
150.degree. C. and pressures from about 50 to 3000 psig. The mixtures to 
be hydrogenated may contain ammonia, caustic or solvents such as methanol, 
tetrahydrofuran, dioxane, butanol and/or isopropanol. 
Although the presence of a strongly basic material in the reaction mixture 
of the present process is not essential, the addition of a strong base 
increases the reaction rate of the process. Strongly basic materials that 
may be used to increase the reaction rate of the present process include 
water soluble alkali metal hydroxides, alkaline earth metal hydroxides, 
tertiary amines including 1,3-dimethyl-piperidine, triethylamine and 
pyridine, Lewis bases, strongly basic ion exchange resins and basic 
aluminas and zeolites. An example of a strongly basic ion exchange resin 
is AMBERLYST A26 ion exchange resin available from Rohm & Haas. A 
preferred Lewis base for the present process is KF. 
The present process may also be carried out with a solvent present, alone 
or in combination with water, in the reaction mixture. Such solvent needs 
to be inert under the reaction conditions of the process. That is the 
solvent should not be a material or mixture that will add or otherwise 
react non-reversibly with the subject pentenenitriles. Preferred solvents 
include dioxane, tetrahydrofuran, dimethylformamide, dimethylacetamide, 
methanol, butanols and isopropanol. If a solvent is used in the reaction 
mixture, it is preferred that the solvent is combined with water and that 
the concentration of water in the reaction mixture be between 15 and 60% 
by weight. This concentration of water aids in maintaining a good reaction 
rate and good selectivity to the desired product. The present process, 
even without the addition of a solvent (for example, the reaction could be 
run in a liquid alkylamine or be run under pressure), has a faster rate 
and improved selectivity if it is run in the presence of water. It is 
preferred that the concentration of the water in the reaction mixture be 
between about 15 and 60% by weight. Water need not be present in the 
reaction mixture for the reaction of the present process to take place 
although the presence of water is beneficial to the process. 
The reaction of the present process is carried out at temperatures from 
about 25 to 200.degree. C. and at pressures from autogeneous to pressures 
of about 1500 psig. Typically the autogeneous pressure of the present 
process may reach a pressure of about 1000 psig. The present reaction may 
be run as a continuous reaction, for example, using a continuous stirred 
tank reactor, a trickle bed or a plug-flow reactor, or as a batch 
reaction. 
The weight ratio of 3-pentenenitrile to 4-pentenenitrile in the present 
process may be from 0 to 1 to 1 to 0. The preferred molar ratio of ammonia 
or alkylamine to pentenenitrile for the present process is from 0.3 to 3, 
and it is 0.15 to 1.5 for hydrazine to pentenenitrile. Either the cis or 
trans isomers of the 3-pentenenitrile may be used in the present process. 
The present process allows the cyanobutylation of ammonia or an alkylamine. 
Alkylamines suitable for the present process include the class consisting 
of alkylamines having from 1 to 10 carbon atoms, dimethylamine, 
dodecylamine, ethylenediamine, 2-methyl-pentamethylenediamine, 
1,3-diaminopentane, 1,2-diaminocyclohexane, 3-methylpiperidine, 
octadecylamine, hexamethylenediamine, and piperazine. 
Some reaction products formed by the present process include reaction 
products which have the formula: 
##STR1## 
where R and R.sub.1 are alkyl or alkylamino groups and R.sub.2 is alkylene 
.

The following examples illustrate the present invention, but are not 
intended to limit the invention. 
EXAMPLES 
Example 1 
Cyanobutylation of Ammonia with a Mixture of 3- and 4-Pentenenitrile in 
Water 
Fifty grams of a mixture containing 68.4% by weight 3-pentenenitrile and 
12.6% by weight 4-pentenenitrile were charged into a 300 ml stainless 
steel batch stirred autoclave under nitrogen. To the autoclave was also 
added 50 g of aqueous 29% ammonia at room temperature. The autoclave was 
sealed and heated to 100.degree. C. with minimal stirring. At reaction 
temperature, maximum stirring of 1400 rpms commenced. The reaction was run 
in the batch mode at autogeneous pressure for 3 hours. The reaction 
contents were cooled to room temperature and transferred to a separatory 
funnel. After 1 hour, the layers were separated and analyzed by gas 
chromatography on a 50 meter.times.0.53 mm DB-1701 glass capillary column. 
The conversion of 3-pentenenitrile and 4-pentenenitrile was 41.7% and 
92.9%, respectively yielding 3-aminopentanenitrile nitrile in a 
selectively of 90%. 
Example 2 
Cyanobutylation of Ammonia with trans-3-Pentenenitrile in Water 
Forty grams of 95.8% by weight trans-3-pentenentrile was charged into a 300 
ml stainless steel batch stirred autoclave under nitrogen. To the 
autoclave was also added 37.6 g of aqueous 29% ammonia at room 
temperature. The autoclave was sealed and heated to 110.degree. C. with 
minimal stirring. At reaction temperature, maximum stirring of 1400 rpms 
commenced. The reaction was run in a batch mode at autogeneous pressure 
for 5 hours. The reaction contents were cooled to room temperature and 
transferred to a separatory funnel. After 1 hour, the layers were 
separated and analyzed by gas chromatography on a 50 meter.times.0.53 mm 
DB-1701 glass capillary column. The conversion of trans-3-pentenenitrile 
was 32.6% yielding 3-aminopentanenitrile in a selectively of 79.4%. 
Example 3 
Cyanobutylation of Methylamine with trans-3-Pentene-nitrile in Water 
Forty grams of a mixture containing 95.8% by weight 3-pentenenitrile was 
charged into a 300 ml stainless steel batch stirred autoclave under 
nitrogen. To the autoclave was also added 49 g of aqueous 40% methylamine 
at room temperature. The autoclave was sealed and heated to 90.degree. C. 
with minimal stirring. At reaction temperature, maximum stirring of 1400 
rpms commenced. The reaction was run in the batch mode at autogeneous 
pressure for 5 hours. The reaction contents were cooled to room 
temperature yielding a homogeneous solution. The product was analyzed by 
gas chromatography on a 50 meter.times.0.53 mm DB-1701 glass capillary 
column. The conversion of 3-pentenenitrile was 95.6% yielding 
3-methylaminopentanenitrile in a selectively of 95.3%. 
Example 4 
Cyanobutylation of Ammonia with trans-3-Pentene-nitrile in Water Containing 
1,3-Dimethylpiperidine 
Forty grams of 95.8% trans-3-pentenenitrile and 0.8 grams of 
1,3-dimethylpiperidine were charged into a 300 ml stainless steel batch 
stirred autoclave under nitrogen. To the autoclave was also added 37.6 
grams of aqueous ammonia (29% by weight NH.sub.3) while the autoclave was 
at room temperature. 
The autoclave was then sealed and heated to 110.degree. C. with minimal 
stirring. On reaching the reaction temperature stirring at a rate of 1400 
rpms was commenced. The reaction was run in a batch mode for 5 hours at 
autogeneous pressure. The reaction mixture was then cooled to room 
temperature and transferred to a separatory funnel. After 1 hour, the 
layers were separated and analyzed by gas chromatography on a 50 
meter.times.0.53 mm DB-1701 glass capillary column. The conversion of 
trans-3-pentenenitrile was 56.9% yielding 3-aminopentanenitrile and cis 
and trans-2-pentenenitrile at a selectivity of 81.1% and 12%, 
respectively. 
Example 5 
Cyanobutylation of Ammonia with trans-3-Pentene-nitrile in Water Containing 
AMBERLYST A26 Ion Exchange Resin 
Forty grams of 95.8% trans-3-pentenenitrile and 4.0 grams of AMBERLYTE A26 
(strongly basic microreticular ion exchange resin from Rohm & Haas Co.) 
were charged into a 300 ml stainless steel batch stirred autoclave under 
nitrogen. To the autoclave was also added 37.6 grams of aqueous ammonia 
(29% by weight NH.sub.3) while the autoclave was at room temperature. 
The autoclave was then sealed and heated to 110.degree. C. with minimal 
stirring. On reaching the reaction temperature stirring at a rate of 1400 
rpms was commenced. The reaction was run in a batch mode for 5 hours at 
autogeneous pressure. The reaction mixture was then cooled to room 
temperature and transferred to a separatory funnel. After 1 hour, the 
layers were separated and analyzed by gas chromatography on a 50 
meter.times.0.53 mm DB-1701 glass capillary column. The conversion of 
trans-3-pentenenitrile was 52% yielding 3-aminopentanenitrile and cis and 
trans-2-pentenenitrile at a selectivity of 82.4% and 11.5%, respectively. 
Example 6 
Batch Hydrogenation of 3-Aminopentanenitrile with RANEY Cobalt Catalyst 
with Water and Caustic 
In a batch run 96 grams (0.89 mole, 99%) 3-amino-pentanenitrile, 2 grams of 
water and 2.0 grams of a 5% by weight NaOH solution were charged into a 
300 ml stainless steel autoclave equipped with a thermocouple, cooling 
coils, sample dip tube having a 5 micron stainless steel filter and an 
agitator with impeller blade. Such an autoclave is available form 
Autoclave Engineers. Following the charging of the NaOH and 
aminopentanenitrile, 2.0 grams (dry basis) of RANEY cobalt catalyst (RANEY 
2724) was added to the mixture in the autoclave. The autoclave was then 
closed and purged 3 times with hydrogen. The temperature was then raised 
to 90.degree. C. under 50 psig hydrogen pressure with very slow stirring. 
When the temperature of the mixture reached 90.degree. C., the hydrogen 
pressure was increased to 800 psig and stirring at 1200 rpms was 
commenced. At these conditions of temperature and pressure the reduction 
of the aminopentanenitrile to 1.3-diaminopentane required 120 minutes. 
The produce formed in the reaction was analyzed by gas chromatography and 
showed a yield of 99.5% 1,3-diaminopentane.