Novel one-pot Facile Synthesis of Thiopyranopyrazole Using [H mim]HSO4 Catalyst

An efficient and easy protocol has been developed for synthesis of thiopyranopyrazole by using [H mim]HSO4 as recyclable catalyst under solvent-free condition at room temperature. This environmen-tally benign method has advantages, such as high yield of products, simple work-up procedure, and avoidance of the organic solvents, which will contribute in serving as a green process greatly. The catalyst was easily recovered and reused without any considerable loss of activity