4-Methoxybenzyl alcohol → (2S,3R)-3-Allyl-1-(tert-butyl-dimethyl-silanyl)-4-oxo-azetidine-2-carboxylic acid 4-methoxy-benzyl ester

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Reaction Steps

A mixture of 900 mg of crude compound 57 (3.34 mmol) above, EDC hydrochloride salt (1.34 g, 7.01 mmol), DMAP (83 mg, 0.67 mmol) and 4-methoxybenzyl alcohol (1.40 g, 10.1 mmol) in dichloromethane (9 mL) was stirred at room temperature overnight. The solvent was removed in vacuo. The residue was dissolved with ethyl acetate, washed with 5% aqueous KHSO4, water (×2) and brine (×1). The organic layer was dried over Na2SO4, then concentrated to yield the crude 58 with LC purity: 60%. Purification by ISCO silica gel column using 0-20% AcOEt in Hexanes afforded 630 mg of compound 58 (49% yield, 81% purity): 1HNMR (300 MHz, CDCl3): 0.13 (s, 3H), 0.32 (s, 3H), 0.95 (s, 9H), 2.56 (m, 2H), 3.43 (m, 1H), 3.81 (d, J=2.60 Hz, 1H), 3.82 (s, 3H), 4.67 (s, 2H), 5.17 (m, 2H), 5.72 (m, 1H), 6.94 (d, 2H), 7.34 (d, 2H). Anal. C21H31NO4Si, Mol. Wt.: 389.56. Found: ESI-MS: 390.0 (M+H)+.

Provenance & Evidence