To a solution of 3-[2-(trifluoromethyl)-4′-methoxybenzhydryloxy]azetidine (157) (100 mg, 0.30 mmol) in anhydrous DCM (4 mL) was added MP-carbonate (3.01 mmol/g; 100 mg, 0.30 mmol) and tert-butyl isocyanate (35 μL, 0.30 mmol). The resultant mixture was shaken at ambient temperature for 5 h, after which time it was poured onto a DCM-wetted SCX-2 (1 g) cartridge. The sample was eluted with DCM (6 mL) followed by DCM-MeOH (6 mL), then evaporated. Purification by flash column chromatography [SiO2; ethyl acetate-iso-hexane (35:65→50:50)] afforded the desired product as a colourless glass (90 mg, 70%).
