反应详情

To a solution of triphosgene (223 mg) in chloroform (5 ml), a solution of triethylamine (0.31 ml) and 3,4-dihydro-2H-1,4-benzoxazine obtained in Reference Example 14 (203 mg) in chloroform (2 ml) was added under ice cooling and stirred at the same temperature for 10 minutes. To the reaction mixture, methyl 4-aminoadamantane-1-carboxylate obtained in Reference Example 11 (314 mg) and triethylamine (0.31 ml) were then added and stirred under ice cooling for 3 hours. The reaction mixture was warmed to room temperature and further stirred for 16 hours. The reaction mixture was diluted with ethyl acetate, and the organic layer was washed sequentially with water, 1M aqueous hydrochloric acid, saturated aqueous sodium bicarbonate and brine. After drying over anhydrous magnesium sulfate, the desiccant was filtered off and the solvent was distilled off under reduced pressure. The resulting residue was purified by silica gel column chromatography (eluting solvent: n-hexane:ethyl acetate=4:1 to 1:1) to give an isomer mixture of the titled compounds (a mixture of Compounds 35a and 35b, 474 mg) as a light-yellow amorphous substance.

1. additionwas added under ice cooling
2. additionwere then added
3. stirringstirred under ice cooling for 3 hours
4. stirringfurther stirred for 16 hours
5. washthe organic layer was washed sequentially with water, 1M aqueous hydrochloric acid, saturated aqueous sodium bicarbonate and brine
6. dry with materialAfter drying over anhydrous magnesium sulfate
7. filtrationthe desiccant was filtered off
8. distillationthe solvent was distilled off under reduced pressure
9. customThe resulting residue was purified by silica gel column chromatography (eluting solvent: n-hexane:ethyl acetate=4:1 to 1:1)
10. customto give