反应详情

A solution of N-[(1,1-dimethylethoxy)carbonyl]-3-[(9H-fluoren-9-ylmethoxy)carbonyl]amino-L-alanine (5.00 g, 11.7 mmol) in N,N-dimethylformamide (10 mL) was treated with potassium hydrogen carbonate (1.4 g, 14.1 mmol) and iodomethane (0.8 ml, 12.9 mmol). The reaction mixture was stirred at room temperature for 2 h. Then water was added and the mixture was extracted three times with ethyl acetate. The combined organic layers were washed with brine, dried (Na2SO4), concentrated and chromatographed (10–40% ethyl acetate/hexanes) to give N-[(1,1-dimethylethoxy)carbonyl]-3-[(9H-fluoren-9-ylmethoxy)carbonyl]amino-L-alanine, methyl ester (4.20 g, 81%) as a white solid.

1. extractionthe mixture was extracted three times with ethyl acetate
2. washThe combined organic layers were washed with brine
3. dry with materialdried (Na2SO4)
4. concentrationconcentrated
5. customchromatographed (10–40% ethyl acetate/hexanes)