Acetic Acid → 1-Benzyl-2-methyl-azetidine-2-carboxylic acid ethyl ester

関与物質

反応条件

反応手順

A solution of 2-[benzyl-(2-chloro-ethyl)-amino]-propionic acid ethyl ester (1 eq.) in dry THF was cooled to −78° C. under nitrogen. KHMDS (15% w/w in toluene) (1.25 eq.) was slowly added so that temperature was kept below −65° C. The reaction was stirred for 1 h at −70° C. Then acetic acid (0.3 eq.) was added. The reaction was warmed to 20° C. and stirred for 10 min, then quenched with a saturated aqueous solution of NaHCO3 and partially concentrated under reduced pressure. The crude was extracted twice with DCM. The organic layers were combined, dried over MgSO4, filtered and concentrated under reduced pressure. The crude was purified by chromatography on silica gel (elution with heptane/EtOAc 1/0 then 95/5) to afford 1-benzyl-2-methyl-azetidine-2-carboxylic acid ethyl ester.

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