Patent ID: 7652165
Filing Date: 2010-01-26
Classification: C07C

Abstract:
1. A process for preparing 3-cyano-3,5,5-trimethylcyclohexanone (isophoronenitrile), comprising reacting isophorone with hydrogen cyanide in the presence of a base as a catalyst to form a crude isophoronenitrile product, and subsequently distilling the crude isophoronenitrile product to prepare the isophoronenitrile, wherein the base is selected from the group consisting of an alkali metal cyanide, an alkaline earth metal cyanide, an alkali metal hydroxide, an alkaline earth metal hydroxide, an alkali metal oxide, an alkaline earth metal oxide, an alkali metal alcoholate and an alkaline earth metal alcoholate, wherein, before the distilling, at least one sulfonic acid is added, wherein the at least one sulfonic acid is selected from the group consisting of methanesulfonic acid, a naphthalenesulfonic acid, an alkyl-substituted naphthalenesulfonic acid, an alkyl-substituted benzenesulfonic acid having an alkyl radical having greater than or equal to 4 carbon atoms, and combinations thereof, and wherein the addition of the at least one sulfonic acid neutralizes the base in such a way that no sedimenting precipitates occur.