Trifluoroacetic acid → 1-[1-(3-Methoxy-4-nitrophenyl)piperidin-4-yl]-4-methyl-1,4-azaphosphinane 4-oxide

Participants

Reaction Conditions

Reaction Steps

To a stirring solution of tert-butyl 4-(4-methyl-4-oxido-1,4-azaphosphinan-1-yl)piperidine-1-carboxylate (178 mg, 0.563 mmol) in CH2Cl2 (2 mL) was added trifluoroacetic acid (0.5 mL). After 20 min, the solution was concentrated and the resulting residue was redissolved in DMF (2 mL). Potassium carbonate (160 mg, 1.16 mmol) was added portionwise to the stirring solution followed by 5-fluoro-2-nitroanisole (158 mg, 0.930 mmol). The reaction mixture was heated to 50° C. After 2 h, the reaction mixture was concentrated and the residue was purified by silica gel chromatography (0-10% 7N ammonia in methanol:dichloromethane) to afford the compound as a bright yellow solid (176 mg, 86% yield).

Provenance & Evidence