反应详情

To a mixture of 0.8 g (2.2 mmol) of O-(9-phenyl-9H-fluoren-9-yl)-L-serine methyl ester (Example 4a, Step 2) and 1.2 g (8.9 mmol) of potassium carbonate in acetonitrile (5 mL) was added 0.17 mL (2.7 mmol) iodomethane and the mixture stirred at room temperature for 16 h. The mixture was dissolved in dichloromethane, filtered and after evaporation of the solvent the residue was chromatographed on silica gel with 60% ethyl acetate in hexanes to give 0.038 g (yield 4.5%) N-Methyl--O--(9-phenyl-9H-fluoren-9-yl)-L-serine methyl ester as an oil. 1H NMR (CDCl3, 300 MHz) δ: 7.67 (d, 2H), 7.45-7.10 (m, 11H), 3.73 (s, 3 H), 3.35-3.15 (m, 3H), 2.37 (s, 3H), 2.06 (s, 1H); 13C NMR (CDCl3, 75 MHz) 6: 173.2, 146.6, 146.4, 143.1, 140.6, 129.2, 129.1, 128.3, 128.1, 128.0, 127.1, 125.4, 125.3, 125.1, 119.9, 88.3, 63.8, 62.9, 51.7.

1. filtrationfiltered
2. customafter evaporation of the solvent the residue
3. customwas chromatographed on silica gel with 60% ethyl acetate in hexanes