Regioselectivity in the multicomponent reaction of 5-aminopyrazoles, cyclic 1,3-diketones and dimethylformamide dimethylacetal under controlled microwave heating

• DOI: 10.3762/bjoc.8.3
• Publication Date: 2012-01-04T19:49:28Z
• Authors: Kamal Usef Sadek; Ramadan Ahmed Mek...; Tahany Mahmoud Mo...; Moustafa Sherief ...; Mohamed Hilmy Eln...
• Keywords: QD241-441; regioselectivity; Science; Q; Organic chemistry; DMFDMA; dimedone; aminopyrazoles; 01 natural sciences; Full Research Paper; 0104 chemical sciences

The multicomponent reaction of 5-aminopyrazole derivatives with cyclic 1,3-dicarbonyl compounds and dimethylformamide dimethylacetal (DMFDMA) in DMF at 150 °C under controlled microwave heating afforded regioselectively 8,9-dihydropyrazolo[1,5-a]quinazolin-6(7H)-ones 6 rather than the corresponding dihydropyrazolo[5,1-b]quinazolin-8(5H)-ones 4.