反应详情

To a solution of methyl 2-(tert-butoxycarbonyl)-2-(dimethoxyphosphoryl)acetate (5255 mg, 17678 μmol) in 25 mL of DCM at 0° C. was added DBU (2665 μl, 17678 μmol) dropwise. To the mixture was then added a solution of 2,2-dimethylbenzo[d][1,3]dioxole-5-carbaldehyde (3000 mg, 16836 μmol) in 10 mL of DCM over 5 minutes so as to maintain internal temperature below 10° C. The reaction was warmed to rt and stirred overnight before being diluted with DCM (25 mL) and poured in saturated ammonium chloride (100 mL). The aqueous layer was extracted with DCM (1×50 mL). The combined organic layers were washed with 10% aqueous sodium bicarbonate then water then brine and dried over Na2SO4. Concentration under reduced pressure and purification by silica gel provided (Z)-methyl 2-(tert-butoxycarbonyl)-3-(2,2-dimethylbenzo[d][1,3]dioxol-5-yl)acrylate (5005 mg, 85.1% yield) as a white solid.

1. temperatureto maintain internal temperature below 10° C
2. extractionThe aqueous layer was extracted with DCM (1×50 mL)
3. washThe combined organic layers were washed with 10% aqueous sodium bicarbonate
4. dry with materialwater then brine and dried over Na2SO4
5. concentrationConcentration
6. customunder reduced pressure and purification by silica gel