反应详情

To a 0° C. solution of D-penicillamine methyl ester hydrochloride (0.250 g., 1.25 mmoles) in DMF (4 mL) was added DBU (0.382 ml., 2.56 mmoles), followed by methyl iodide (0.081 ml., 1.31 mmoles). After 1 hour, the solution was partitioned between brine and ethyl acetate, and the organic layer was dried over sodium sulfate and concentrated. The residue was purified on silica, eluting with 6% methanol in dichloromethane to give S-methyl-D-penicillamine methyl ester as a colorless oil in 81% yield: 1H--NMR (CDCl3) δ 1.25 (s, 3H) 1.35 (s, 3H), 2.02 (s, 3H), 3.44 (s,1H), 3.72 (s, 3H); FAB HRMS:expected (M+H)=178.0902, found (M+H)=178.0905.

1. customthe solution was partitioned between brine and ethyl acetate
2. dry with materialthe organic layer was dried over sodium sulfate
3. concentrationconcentrated
4. customThe residue was purified on silica
5. washeluting with 6% methanol in dichloromethane