facile ionic liquidmediated, multi component synthesis of dihydro-1h-furo[2,3-c]pyrazoles

A facile, convenient, efficient, and high-yielding diastereoselective synthesis of a novel fused dihydro-1h-furo[2,3-c]pyrazole by a one-pot fourcomponent reaction of β-keto ester, hydrazine, aromatic aldehyde and pyridinium salt in the presence of [bmim]oh ionic liquid medium provided with excellent yields. three new bonds (two c‒c and one c‒o), and two stereo centres are generated in a single operation. low cost, short reaction time, excellent yield, operational simplicity, and more importantly the purification of the compounds by a non-chromatographic method make this process very significant for academic research and practical applications.