Vacuum–thermal fragmentation and ring cleavage of 1-(N-substituted-pyrrol-2-yl)-3-tosyltriazene tetraalkylammonium salts to 4-cyano-1-azabuta-1,3-dienes

Abstract

N-Methyl- and N-phenyl-4-cyano-1-azabuta-1,3-diene (1a and 1b respectively) are produced by vacuum–thermal fragmentation and ring cleavage of 1-(N-substituted-pyrrol-2-yl)-3-tosyltriazene tetraalkylammonium salts, prepared by reaction of the corresponding 2-lithiopyrroles with tosyl azide and successive reaction of the resulting lithium triazene salts with tetraalkylammonium bromide.