A simple and catalyst free one pot access to the pyrazolone fused 2,8-dioxabicyclo[3.3.1]nonanes

Abstract

Synthesis of a series of novel aryl and heteroaryl fused 2,8-dioxabicyclo[3.3.1]nonanes (3) was accomplished by one pot, catalyst free reaction of 2-hydroxy chalcone (1) with 3-trifluoromethyl substituted pyrazolone (2) in xylene at reflux temperature. The role of the trifluoromethyl functional group in formation of 3 was confirmed by comparative studies with 3-methyl substituted pyrazolones (2c,d) and the outcome is presented.