Abstract
A series of 6-amino-4-aryl-3-methyl-2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitriles (5a–5j) were synthesized by four-component one-pot reaction of methyl acetoacetate (or ethyl acetoacetate), hydrazine hydrate, arylaldehydes and malononitrile in the presence of phase transfer catalyst. A highest yield of product was obtained while using 30 mol % of HDBAC as a catalyst.
Keywords: Four-component reaction, one-pot synthesis, phase-transfer catalysis, pyrano[2, 3-c]pyrazole, phase-transfer catalysis, Multi component reaction (MCR), bioactive, pharmacological, Green method, catalyst, CN moiety