Syntheses of hydrazones 5a-t (Scheme I)(7 7-76, 78), which are the precursors of hydrazMoyl halides, have been accomplished by employing two distinct approaches, one of which comprises the condensation of aliphatic or aromatic aldehydes with 2, 4dinitrophenylhydrazine in alcohol at room temperature (75) while the other involves the coupling reaction of aryldiazonium salts with ethylacetoacetate or acetylacetone (72, 76).