Tetrahydrofuran → 3-(3-Fluoro-5-chloro-2-pyridyl)-4-amino-5difluoromethoxy-1-methyl-[1H]-pyrazole

Participants

Reaction Steps

4.2 g of 3-(3-fluoro-5-chloro-2-pyridyl)-4-nitro-5-difluoromethoxy-1-methyl-[1H]-pyrazole (Example H47) are initially introduced into the reaction vessel together with 40 ml of tetrahydrofuran, and 5.8 g of Raney nickel in ethanol are added. Hydrogenation is carried out under normal pressure and at a temperature of 30-35° C. After uptake of 728 ml of hydrogen, the hydrogenation is interrupted and the reaction mixture is filtered over Hyflo. After removal of the solvent in vacuo, 3.15 g of the desired title compound are obtained as a brown solid of melting point 92-94° C.

Provenance & Evidence