Synthesis of new pyrazoline derivatives II reaction of Erythro-2,3-dibromoketones with nicotinic and isonicotinic acid hydrazides

The reaction of a series of erythro-2, 3-dibromo-1, 3-diaryl-1-propanones 1 a-g with 2 molar equivalents of nicotinic and isonicotinic acid hydrazides afforded 4-bromo-1-nicotinoyl and 1-isonicotinoyl-3, 5-diaryl-2-pyrazolines 2 a-g and 3 a-g, respectively. The structure of the products was confirmed by chemical and spectral tools. The mechanism of the reaction was discussed