Method for the production of aminocyanoacetamide
AssigneeLonza Ltd.
InventorsHans P. Mettler, Felix Previdoli
Life of this patent
Estimating the term…
Abstract
A large-scale industrial process for the production of aminocyanoacetamide is disclosed. A starting material is cyanoacetic acid ester, which is treated with a nitrous acid in a first step to a corresponding hydroxy-iminocyanoacetic acid ester. The hydroxy-iminocyanoacetic acid ester is then hydrogenated and, in a following step, treated with ammonia for obtaining the final product aminocyanoacetamide.
Claims18
A method for the production of aminocyanoacetamide comprising
- nitrosating a member selected of the group consisting of cyanoacetic-acid-(C.sub.1 -C.sub.4)-alkyl ester, cyanoacetic-acid-aryl-(C.sub.1 -C.sub.4)-alkyl ester and mixtures thereof with an alkali metal nitrite to form a corresponding hydroxy-iminocyanoacetic acid ester;
- hydrogenating the hydroxy-iminocyanoacetic acid ester with hydrogen to aminocyanoacetic acid ester in the presence of a platinum hydrogenation catalyst under a pressure of from 1 to 100 bar and at temperatures from between about 0.degree. to 40.degree.;
- reacting the aminocyanoacetic acid ester with aqueous ammonia to the final product;
- employing platinum placed in amounts of from 1 to 20 weight-percent onto aluminum oxide, platinum placed in amounts of from 1 to 20 weight-percent onto silicon dioxide, platinum placed in amounts of from 1 to 20 weight-percent onto barium sulfate, platinum placed in amounts of from 1 to 20 weight-percent onto calcium carbonate, platinum placed in amounts of from 1 to 20 weight-percent onto carbon, and mixtures thereof, as said platinum hydrogenation catalyst.
A method for the production of aminocyanoacetamide, wherein a cyanoacetic-acid-(C.sub.1 -C.sub.4)-alkyl ester or an aryl alkyl ester in the presence of an acid is treated with an alkali metal nitrite to form a corresponding hydroxy-iminocyanoacetic acid ester, wherein this hydroxy-iminocyanoacetic acid ester is hydrogenated with hydrogen to aminocyanoacetic acid ester in the presence of a platinum hydrogenation catalyst and wherein the hydrogenation is performed under a pressure of from 1 to 100 bar and at temperatures from about 0.degree. to 45.degree. and wherein the aminocyanoacetic acid ester is finally reacted with aqueous ammonia to the final product;
- employing platinum placed in amounts of from 1 to 20 weight-percent onto aluminum oxide, platinum placed in amounts of from 1 to 20 weight-percent onto silicon dioxide, platinum placed in amounts of from 1 to 20 weight-percent onto barium sulfate, platinum placed in amounts of from 1 to 20 weight-percent onto calcium carbonate, platinum placed in amounts of from 1 to 20 weight-percent onto carbon, and mixtures thereof, as a platinum hydrogenation catalyst.
Dependencies are inferred from the claim text.