Synthesis of l,2-Diazol-4-sulfonamides, 1,2,4- and l,2,5-Oxadiazol-3-sulfonamides, l,2,3-Triazol-4-sulfonamides, and Pyrimidine-5-sulfonamides starting from Cyanomethanesulfonyl Chloride

摘要

Cyanomethanesulfonyl chloride was reacted with amines yielding cyanomethanesulfon-amides which could be transformed into alkoxymethylidene and aminomethylidene derivatives. The reaction of alkoxymethylidene derivatives with phenylhydrazine resulted in the formation of 5-aminopyrazol-4-sulfonamides, whereas from cyanomethanesulfonamides via the N-hydroxyamidine derivatives and their reaction with esters 1,2,4-oxadiazol-3-methanesulfonamides became accessible. Nitrosation of cyanomethanesulfonamides yielded 2-hydroxyimino derivatives which were then transformed into 2-hydroxyimino N-hydroxyamidine derivatives, and finally cyclized into 4-amino-1,2,5-oxadiazol-3-sulfonamides. On the other hand diazotation of cyanomethanesulfonamides gave the 2-arylhydrazono derivatives, which after transformation into N-hydroxyamidine derivatives gave by reaction with POCl_3 5-amino-1,2,3-triazol-4-sulfonamides. Finally, the reaction between cyanomethanesulfonamides and formamidinium acetate opened an easy access to 4-aminopyrimidine-5-sulfonamides, which could be transformed by trialkyl orthoformiates into substituted pyrimidino[4,5-e][1,2,4]thia-diazine derivatives. All intermediates as well as transformation products of the heterocyclic systems were isolated and well characterized. Mechanisms were discussed, and the stereochemistry, when necessary and possible, was elucidated.