AN EASY ACCESS TO 2-OXOHYDRAZONES VIA ELECTROPHILIC ALPHA-P-TOLYLHYDRAZONYLATION OF KETONE ENOLATES WITH TERT-BUTYL P-TOLYLAZO SULFIDE

The title reaction conveniently furnishes, as the sole or main products, alpha-(p-tolylhydrazono)ketones or their N-methylderivatives (H+ or Mel quenching of the final mixture, respectively). Although the method fails with ketones having a secondary alkyl group bonded to the carbonyl, yields are otherwise more than satisfactory and particular interest is attached to the hydrazonylation of the methyl group in methyl ketones.