| 摘要 |
In a process for the manufacture of addition products of hydrocyanic acid with acrylic acid nitrile by reacting acrylic acid nitrile in aqueous solution with a water-soluble inorganic salt of hydrocyanic acid having an alkaline reaction, the reaction is conducted in the presence of a proportion of an acid which is at least as strong as acetic acid such that the greater part of the hydroxide formed during the reaction is neutralized. Water soluble inorganic salts of hydrocyanic acid mentioned as starting materials are alkali metal cyanides such as sodium cyanide or potassium cyanide, alkaline earth metal cyanides such as calcium cyanide or ammonium cyanide. For neutralizing the hydroxides formed during the reaction there may be used inorganic acids such as hydrochloric, sulphuric or phosphoric acids or organic acids such as formic acid or acetic acid. The reaction product consists principally of succinic acid dinitrile and succinimide which may be isolated or hydrolysed directly to succinic acid. In examples: (1) acrylic acid nitrile in glacial acetic acid is dropped into heated aqueous sodium cyanide, succinic acid dinitrile and succimide are separated from the two layers formed or the reaction mixture is hydrolysed by boiling with aqueous sodium hydroxide and acidifying or boiling with sulphuric acid to obtain succinic acid; (2) acrylic acid nitrile and phosphoric acid are run into warm aqueous sodium cyanide and the heating is continued. By hydrolysing the products with acid or alkaline media succinic acid is obtained. Sulphuric acid is also employed instead of phosphoric acid. |
