反应详情

To an ice-bath cooled mixture of phenoxyacetic acid 2-(toluene-4-sulfonyl)ethyl ester (Intermediate 3, 3.0 g) and 1 mL of CH2Cl2 was added drop-wise 3.0 mL of chlorosulfonic acid (5.2 g, 5.0 eq). After the addition of the chlorosulfonic acid was complete the ice bath was removed. The mixture was continued to stir at room temperature for 3 h. Thereafter the thick syrupy mixture was poured onto the crushed ice with vigorous stirring. White precipitates were collected by filtration, were washed with methanol and cold benzene, and dried overnight under high vacuum to yield 3.4 g (87%) of Intermediate 4 as white powder.

1. temperatureTo an ice-bath cooled
2. customwas removed
3. additionThereafter the thick syrupy mixture was poured onto the crushed ice with vigorous stirring
4. customWhite precipitates
5. filtrationwere collected by filtration
6. washwere washed with methanol and cold benzene
7. customdried overnight under high vacuum