General procedure for the synthesis of 1-Benzyloxycarbonyl-3-hydroxyazetidin-3-one from 1-Benzyloxycarbonylazetidin-3-one: Triphenylmethyl-3-hydroxyazetidin-1-carboxylate (3.5 g, 0.0168 mol) was dissolved in dichloromethane (100 mL) at room temperature, followed by the addition of Dess-Martin periodinane (10.7 g, 0.025 mol). The reaction mixture was stirred at room temperature for 5 hours. Upon completion of the reaction, the reaction was quenched with a 1:1 ratio of saturated aqueous sodium bicarbonate and 1 M sodium thiosulfate solution (200 mL). The mixture was extracted with dichloromethane and the organic layer was separated. The organic layer was dried with anhydrous magnesium sulfate and subsequently concentrated under reduced pressure to afford phenylmethyl 3-oxoazetidine-1-carboxylate (3.43 g, 99% yield), the product was a clear, colorless oil, which did not require further purification. The product was confirmed by 1H NMR (400 MHz, CDCl3): δ 7.39-7.31 (m, 5H), 5.17 (s, 2H), 4.77 (s, 4H). Mass spectrometry (EI) analysis was consistent with the molecular weight of C11H11NO3: 205 (M+).
