反应详情

温度

0 °C

Crude 5,5-dimethyl-5′-nitrospiro[[1,3]dioxane-2,3′-indolin]-2′-one (obtained as described in Example 17, Step 1) (361 mg) was dissolved in dry DMF (11 ml) and cooled to 0° C.; NaH (60% w/w dispersion in mineral oil, 83 mg, 2.076 mmol) was added; and the mixture was stirred at 0° C. for 10 minutes (the reaction turned dark orange). Methyl 2-bromoacetate (0.144 ml, 1.557 mmol) was then added, the reaction was warmed to room temperature and stirred for 3 hours. The solvent was evaporated, water was added and extracted with EtOAc; the combined organic layers were dried over Na2SO4, filtered and evaporated. The crude was purified by flash chromatography on silica gel cartridge (petroleum ether:EtOAc from 95:5 to 85:15) affording methyl 2-(5,5-dimethyl-5′-nitro-2′-oxospiro[[1,3]dioxane-2,3′-indoline]-1′-yl)acetate (344 mg, 0.982 mmol, 84% yield). MS/ESI+ 351.0 [MH]+.

1. temperaturethe reaction was warmed to room temperature
2. stirringstirred for 3 hours
3. customThe solvent was evaporated
4. additionwater was added
5. extractionextracted with EtOAc
6. dry with materialthe combined organic layers were dried over Na2SO4
7. filtrationfiltered
8. customevaporated
9. customThe crude was purified by flash chromatography on silica gel cartridge (petroleum ether:EtOAc from 95:5 to 85:15)