Trifluoroacetic acid → HCID 66875459, compound

Participants

Reaction Steps

A slurry of tert-butyl 4-(3-hydroxybenzylidene)piperidine-1-carboxylate (500 mg, 1.73 mmol), phenylboronic acid (418 mg, 3.43 mmol), cupric acetate (314 mg, 1.73 mmol), triethyl amine (1.21 mL 1.8 mmol), and 4 Å powdered sieves (300 mg) in dichloromethane (15 mL) was stirred 18 h at ambient temperature. The reaction mixture was diluted with additional solvent and filtered to remove solid material, washed successively with 1N NaOH and brine, and dried over Na2SO4 to provide a brown oil. This material was purified by column chromatography (1:4 ethyl acetate:heptane) to provide the intermediate Boc-protected material (190 mg, 33%). This material was dissolved in dichloromethane (20 mL) and stirred with trifluoroacetic acid (1 mL) for 3 d at ambient temperature. The reaction was concentrated to a foam that was dissolved in toluene and re-evaporated to give the title compound which was used in the next reaction.

Provenance & Evidence