Abstract
The reaction of O-methyl thiocarboxylates 8a, b with organic azides at 110°C yielded the corresponding imidates of type 9, which were easily hydrolyzed to give amides 10. The formation of 9 can be rationalized by a 1,3-dipolar cycloaddition of the azide with the C=S group, followed by the 'two-fold extrusion' of N2 and S. The analogous reaction with methyl dithiobenzoate (11) led to thioimidates 13. On heating, the latter were transformed into thioamides 12.