申请人:Deutsche Gold- und Silber-Scheideanstalt vormals Roessler
公开号:US04028406A1
公开(公告)日:1977-06-07
Improvements in the process of preparing penicillamine or a homolog thereof by reacting an .alpha.-carbon atom branched aldehyde, sulfur and ammonia to form a thiazoline-.DELTA..sup.3, reacting the thiazoline-.DELTA..sup.3 with anhydrous hydrogen cyanide to form a thiazolidine-4-carbonitrile, hydrolyzing the nitrile to form a mixture of the salt of the thiazolidine-4-carboxylic acid and ammonium salts, separating off the ammonium salts and hydrolytically decomposing the thiazolidine-4-carboxylic acid, wherein under the action of a mineral acid the thiazolidine-4-carbonitrile is in the first stage converted at low temperatures into the salt of the thiazolidine-4-carbonamide and then at higher temperatures converted into the salt of the thiazolidine-4-carboxylic acid.