反应详情

温度

0 °C

MSH 1 (439 mg, 2.0 mmol) was added to a 10 mL round bottom flask and dissolved in DMF (3 mL). In a separate vial, N-(tert-butoxycarbonyl)-L-cysteine methyl ester 2 (48 mg, 0.20 mmol) was added and dissolved in DMF (3 mL). The vial was cooled to 0° C. and a solution of potassium carbonate (138 mg, 1.0 mmol) in water (3.0 mL) was added. The resulting solution was added dropwise by pipette over a period of 3 min to the stirred MSH solution at room temperature. The vial was rinsed with DMF (2×1 mL) to ensure complete transfer. TLC (petrol:ethyl acetate, 4:1) analysis after completion of the addition revealed a single, UV active product (Rf 0.6). The reaction mixture was transferred to a separatory funnel and diluted with diethyl ether (150 mL) and water (100 mL). After separation, the organic layer was washed successively with water (80 mL) and brine (80 mL) before drying (MgSO4) and filtering. The solvent was removed under reduced pressure and the resulting residue purified by column chromatography to provide methyl 2-[(tert-butoxycarbonyl)amino]acrylate 3 as a clear oil (40 mg, 98%).

1. additionThe resulting solution was added dropwise by pipette over a period of 3 min to the stirred MSH solution at room temperature
2. washThe vial was rinsed with DMF (2×1 mL)
3. additionTLC (petrol:ethyl acetate, 4:1) analysis after completion of the addition
4. customThe reaction mixture was transferred to a separatory funnel
5. additiondiluted with diethyl ether (150 mL) and water (100 mL)
6. customAfter separation
7. washthe organic layer was washed successively with water (80 mL) and brine (80 mL)
8. dry with materialbefore drying (MgSO4)
9. filtrationfiltering
10. customThe solvent was removed under reduced pressure
11. customthe resulting residue purified by column chromatography