Process for the manufacture of methyl limonitrile

摘要

The present invention is directed to a process for the manufacture of methyl limonitrile comprising a mixture of 3,7-dimethyl-2,6-nonadiene nitrile, 3,7-dimethyl-3,6-nonadiene nitrile and 7-methyl-3-methylene-6-nonene nitrile comprising the following steps: a) reacting 6-methyl-5-octen-2-one with cyano acetic acid and removing carbon dioxide and water, wherein the reaction and the removal of carbon dioxide and water are performed in the presence of a base and a co-base 1 in an organic solvent, and wherein the organic solvent is a solvent which forms a heteroazeotrop with water; b) removing the solvent and the base of the reaction mixture obtained after having performed step a) or step c) by distillation to obtain a reaction mixture, whereby this step may optionally be performed in the presence of a co-base 2; c) isomerizing the reaction mixture obtained after having performed step a) or step b) to obtain an isomerized reaction mixture in the presence of a co-base 2; whereby step b) can be performed before or after step c).

主权项

1. A process for the manufacture of methyl limonitrile comprising a mixture of 3,7-dimethyl-2,6-nonadiene nitrile, 3,7-dimethyl-3,6-nonadiene nitrile and 7-methyl-3-methylene-6-nonene nitrile, wherein the process comprises the following steps:
a) reacting 6-methyl-5-octen-2-one with cyano acetic acid and removing carbon dioxide and water, wherein the reaction of 6-methyl-5-octen-2-one with cyano acetic acid and the removal of carbon dioxide and water are performed in the presence of a base and a co-base 1 in an organic solvent which forms a heteroazeotrop with water; b) removing the organic solvent and the base of a mixture obtained after having performed step a) or step c) by distillation, optionally in the presence of a co-base 2; and c) isomerizing the mixture obtained after having performed step a) or step b) in the presence of a co-base 2 to obtain an isomerized reaction mixture; wherein step b) can be performed before or after step c), and wherein the co-base 2 is selected from the group consisting of 1,4-diaminobutane, 1,5-diaminopentane, piperidine and mixtures thereof.