Sodium borohydride → benzyl ((2S,3S)-1-(2,4-dimethoxybenzyl)-2-(hydroxymethyl)-4-oxoazetidin-3-yl)carbamate

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Reaction Conditions

Reaction Steps

To a solution of benzyl ((2S,3S)-1-(2,4-dimethoxybenzyl)-2-formyl-4-oxoazetidin-3-yl)carbamate (218 g, 0.546 mol) in a mixture of DCM:MeOH (4:1, 2.25 L) at 0° C. was added sodium borohydride (41.3 g, 1.09 mol), portion-wise. The resulting mixture was stirred at 0° C. for 2 h, whereupon it was quenched with cold water (1 L) for 30 min and the layers were separated. The aqueous layer was extracted with DCM (3×200 mL) and the combined organic layers were washed with water, brine, dried over Na2SO4 and concentrated in vacuo to afford the title compound (208 g, 95%) as an off white solid. LCMS: m/z=401.2 (M+1); 1H NMR (300 MHz, CDCl3) δ 7.37-7.29 (m, 5H), 7.21-7.18 (m, 1H), 6.46-6.49 (m, 2H), 5.82 (bd, J=9.6 Hz, 1H), 5.18-5.08 (m, 3H), 4.45 (d, J=14.4 Hz, 1H), 4.28 (d, J=14.4 Hz, 1H), 3.83 (s, 3H), 3.79 (s, 3H), 3.76-3.72 (m, 1H), 3.63-3.52 (m, 2H), 1.87 (dd, J=9.6, 4.0 Hz, 1H).

Provenance & Evidence