反应详情

To a mixture of DCC (9.41 g, 46 mmol), DMAP (0.586 g, 4.8 mmol) and N-CBz-L-valine (12.1 g, 48 mmol) in CH2Cl2 (200 mL) at 0° C., was added dropwise a solution of 4-methoxybenzyl 5-hydroxy-2,2-dimethyl-valerate (6.40 g, 24 mmol) in CH2Cl2 (50 mL). After 1 h at 0° C., the temperature of the reaction mixture was allowed to assume room temperature and then the mixture was stirred for 5h at room temperature. The mixture was filtered through a glass filter and the solvent was removed under reduced pressure. The crude product was column chromatographed (silica gel, 1→4% MeOH in CH2Cl2), to give 8.61 g 4-methoxybenzyl 5-(N-CBz-L-valyloxy)-2,2-dimethylvalerate.

1. customto assume room temperature
2. filtrationThe mixture was filtered through a glass
3. filtrationfilter
4. customthe solvent was removed under reduced pressure
5. customchromatographed (silica gel, 1→4% MeOH in CH2Cl2)