Single vessel synthesis of aminoacetonitriles

A process for preparing aminoacetonitriles under anhydrous conditions comprising the steps of:

• (A) reacting trimethylsilyl cyanide and an aldehyde in N,N-dimethylformamide to obtain a silyl blocked cyanohydrin solution, wherein the aldehyde is selected from the group consisting of p-anisaldehyde, thiophene-2-carboxaldehyde, furan-2-carboxaldehyde, benzaldehyde, crotonaldehyde, trimethylacetldehyde, acetaldehyde, 4-methylbenzaldehyde, 4-N,N-dimethylaminobenzaldehyde, 3-pyridinecarboxaldehyde, valeraldehyde, and 2-chlorobenzaldehyde;
• (B) adding 0.5 milligrams to 10 milligrams of water per gram of water miscible amide solvent to the silyl blocked cyanohydrin solution from step (A);
• and
• (C) passing ammonia through the solution from step (B) to obtain an aminoacetonitrile,
• provided steps (A), (B), and (C) are conducted at a temperature of 30.degree. C. to 40.degree. C., and
• further provided that steps (A), (B), and (C) are conducted in the same reaction vessel wherein the silyl blocked cyanohydrin is not isolated and wherein anhydrous means no water is present except that added in step (B).

A process for preparing aminoacetonitriles under anhydrous conditions comprising the steps of:

• (A') reacting trimethylsilyl cyanide with an aldehyde having the formula RCHO in the absence of a solvent to form a silyl blocked cyanohydrin, wherein R is selected from the group consisting of hydrogen, C.sub.1 -C.sub.20 alkyl, C.sub.3 -C.sub.8 cycloalkyl, C.sub.3 -C.sub.8 alkenyl, C.sub.3 -C.sub.8 alkynyl, and C.sub.6 -C.sub.14 aryl, excluding 3-nitrobenzaldehyde;
• (B') adding a water miscible amide solvent to the silyl blocked cyanohydrin formed in step (A') to obtain a solution, wherein the water miscible amide solvent is selected from the group consisting of N,N-dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dimethylpropionamide, N,N-diethylpropionamide, formamide, and combinations thereof;
• and
• (C') passing ammonia through the solution from step (B') to obtain an aminoacetonitrile,
• provided steps (A'), (B'), and (C') are conducted at a temperature of 20.degree. C. to 50.degree. C., and
• further provided that steps (A'), (B'), and (C') are conducted in the same reaction vessel wherein the silyl blocked cyanohydrin is not isolated.

A process for preparing aminoacetonitriles under anhydrous conditions comprising the steps of:

• (A') reacting trimethylsilyl cyanide with an aldehyde in the absence of a solvent to form a silyl blocked cyanohydrin, wherein the aldehyde is selected from the group consisting of p-anisaldehyde, thiophene-2-carboxaldehyde, furan-2-carboxaldehyde, benzaldehyde, crotonaldehyde, trimethylacetaldehyde, acetaldehyde, 4-methylbenzaldehyde, 4-N,N-dimethylaminobenzaldehyde, 3-pyridinecarboxaldehyde, valeraldehyde, and 2-chlorobenzaldehyde;
• (B') adding N,N-dimethylformamide to the silyl blocked cyanohydrin formed in Step (A') to obtain a solution;
• and
• (C') passing ammonia through the solution from step (B') to obtain an aminoacetonitrile,
• provided steps (A'), (B'), and (C') are conducted at a temperature of 30.degree. C. to 40.degree. C., and
• further provided that steps (A'), (B'), and (C') are conducted in the same reaction vessel wherein the silyl blocked cyanohydrin is not isolated.