Phosgene → methyl (5R)-3-[4-(1,1-dioxidothiomorpholin-4-yl)-3,5-difluorophenyl]-2-oxo-5-oxazolidinecarboxylate

Participants

Reaction Steps

A solution of methyl (2R)-3-{[4-(1,1-dioxidothiomorpholin-4-yl)-3,5-difluorophenyl]amino}-2-hydroxypropanoate (Step 1, 1.02 g, 2.90 mmol) in CH2Cl2 (25 mL) and triethylamine (1.0 g, 1.5 mL, 10.5 mmol) is cooled to 0° C. and treated with phosgene (1.94 mL of a 20% solution in toluene, 3.6 mmol). After stirring at room temperature for one hour, the reaction mixture is diluted with CH2Cl2 and washed with dilute NaHCO3, saline, and dried (MgSO4), filtered and concentrated. Chromatography on silica gel (10% acetonitrile-dichloromethane) provides the title compound (0.91 g, 83%), MS (m/z): [M+H]+=391; 1H NMR (300 MHz, CDCl3): δ 3.16-3.20 (m, 4H), 3.64 (m, 4H), 3.88 (s, 3H), 4.06-4.11 (m, 1H), 4.23 (t, 1H), 5.06-5.11 (m, 1H), 7.16 (d, 2H).

Provenance & Evidence