Chemistry of the Enaminone of 1-Acetylnaphthalene under Microwave Irradiation Using Chitosan as a Green Catalyst

摘要

Enaminone >1 was reacted with hydrazonoyl halides >2a-d to yield 3,4-disubstituted pyrazoles >6a-d. Coupling with arenediazonium chlorides afforded the 2-(arylhydrazono)-3-(1-naphthalenyl)-3-oxopropionaldehydes >13a-c. Compounds >13 could be utilized for the synthesis of a variety of arylpyrazoles, arylazolopyrimidines, and pyridazinones via reaction with hydrazines, aminoazoles, and active methylene derivatives, respectively. A comparative study of aforementioned reactions was carried out with chitosan as a basic ecofriendly catalyst under conventional heating as well as under pressurized microwave irradiation conditions.