反应详情

To a cooled solution of Intermediate 68 (3.19 g, 16.95 mmol) in dimethylformamide (20 mL) was added 60% sodium hydride (1.36 g, 33.9 mmol) and 1,6-dibromohexane (5.2 mL, 33.9 mmol). The mixture was stirred at room temperature for 2 hours. The crude was diluted with methylene chloride (50 mL) and washed with water (3×50 mL), dried (MgSO4) and concentrated. The excess of 1,6-dibromohexane was eliminated by distillation at reduced pressure (P=0.15-0.18 mmHg, T=60-65° C.) and the crude was purified by column chromatography with silica gel using methylene chloride as eluent. The title compound was obtained (3.41 g, 57%) as oil.

1. washwashed with water (3×50 mL)
2. dry with materialdried (MgSO4)
3. concentrationconcentrated
4. distillationThe excess of 1,6-dibromohexane was eliminated by distillation at reduced pressure (P=0.15-0.18 mmHg, T=60-65° C.)
5. customthe crude was purified by column chromatography with silica gel