Benzenesulfonyl chloride → Tert-butyl 1-(phenylsulfonyl)azetidin-3-ylcarbamate

Participants

Reaction Steps

To a stirred suspension of tert-butyl azetidin-3-ylcarbamate (4.61 g, contaminated with diphenylmethane 1:1, ˜13.39 mmoles) in dichloromethane (150 mL), was added triethylamine (3.73 mL, 26.77 mmoles) and benzenesulfonyl chloride (2.57 mL, 20.08 mmoles). The reaction was stirred at room temperature for ˜4 hours and became a solution. Sat. ammonium chloride was added to the mixture and the aqueous phase was extracted with dichloromethane (3×). The combined organic layers were dried over anhydrous magnesium sulphate, filtered and concentrated. The residue was precipitated from dichloromethane/hexanes 1:1 to give the title material (1.073 g, ˜26%) as a solid. The mother liquor was concentrated and the residue was purified on Biotage (0 to 20% acetonitrile in dichloromethane) to afford the title material (2.46 g, ˜58%). 1H NMR 400 MHz CDCl3 δ (ppm): 1.42 (9H, s), 3.60 (2H, br s), 4.06 (2H, dd, J=8.7 and 7.7 Hz), 4.35 (1H, br s), 4.70 (1H, br s), 7.60-7.64 (2H, m), 7.68-7.72 (1H, m), 7.86-7.88 (2H, m).

Provenance & Evidence