Acetonitrile → ethyl 1-ethyl-4-fluoro-1H-pyrazole-5-carboxylate

Participants

Reaction Conditions

Reaction Steps

A microwave vial was charged with ethyl 1-ethyl-1H-pyrazole-5-carboxylate (0.2 g) and Selectfluor™ (0.548 g) followed by acetonitrile (3 ml) and acetic acid (0.5 ml). The mixture was heated at 100° C. under microwave irradiation for 120 min. Selectfluor™ (0.548 g) was added and the mixture was heated was heated at 100° C. under microwave irradiation for 60 min. The solvent was removed in vacuo and the residue was partitioned between DCM (15 ml) and water (15 ml) and separated by hydrophobic frit. The aqueous layer was washed with dichloromethane (2×5 ml) and the combined organic layers concentrated in vacuo. Purification by chromatography on silica gel (20 g silica cartridge) eluting with a gradient of 0-50% DCM in cyclohexane over 20 min gave the title compound (67 mg) as a colourless oil.

Provenance & Evidence