Reaction of Metallo S-Alkyl N-Cyanodithioiminocarbonates and Alkyl N-Cyanocarbamates with Hydrazine. A Novel Preparation of 5-Amino-3-mercapto-1,2,4-triazole

Article abstract of DOI:10.1002/jhet.5570350408

Metal salts of S-alkyl-N-cyanodithioiminocarbonates 7 react as electrophiles with hydrazine hydrate to form 5-amino-3-mercapto-1H-1,2,4-triazole 1. The novel 4-cyanothiosemicarbazide 9 is proposed as the intermediate which cyclizes to the aromatic triazole. The rate determining step is addition of hydrazine to the iminocarbonate and is second order. Other nucleophiles such as substituted hydrazines and amines failed to react. Exchange of either or both sulfurs with oxygen leads to decomposition or mixtures of products.