HYDROLYSIS AND HYDRAZINOLYSIS OF ESTERS OF N,N-DIMETHYLDITHIOCARBAMIC ACID: A METHOD FOR THE PREPARATION OF MERCAPTANS

Abstract

A method has been developed for the preparation of mercaptans from alkyl and aralkyl chlorides. This consists of the condensation of sodium N,N-dimethyl-dithiocarbamate with halides followed by alkaline hydrolysis or hydrazinolysis of the resulting N,N-dimethyldithiocarbamates (IV). In the hydrazinolysis of IV, an insoluble solid by-product was formed which was identified as 3-hydrazino-4-amino-5-mercapto-4,1,2-triazole. Although this method was found to have wide scope a few failures were encountered. Nitro-derivatives of IV were sensitive to alkali or hydrazine and yielded only tars on attempted degradation. β-Phenoxyethyl N,N-dimethyldithiocarbamates (IX) were found to possess a labile alkyl–oxygen bond so that in the presence of alkali or hydrazine only the corresponding phenols were formed. The labile nature of the alkyl–oxygen bond ceased abruptly when the alkyl chain of IX was increased so that 3-p-chlorophenoxypropyl and 4-p-chlorophenoxybutyl mercaptans could be prepared in high yields.