反应详情

Methyl ester 6 (2.60 g, 10.1 mmol) was dissolved in a 3:1:1 mixture of MeOH-THF—H2O. LiOH.H2O (0.53 g, 12.6 mmol) was added at room temperature and the reaction allowed to stir for 3 h. All solvents were evaporated, apart from water. The remaining aqueous solvent was diluted further and thoroughly washed with ethyl acetate. The aqueous basic aqueous layer was then acidified to pH 2 with 1 M HCl and the product extracted with ethyl acetate. The organic layers were then combined and dried over Na2SO4, filtered and concentrated to afford the title compound. (2.33 g, 95%): δH (400 MHz, CDCl3) 2.43 (s, 3H, CH3), 2.87 (s, 3H, CH3), 3.99 (s, 2H, CH2), 7.32 (d, J=8.0 Hz, 2H, CH), 7.69 (d, J=8.0 Hz, 2H, CH); δC (100 MHz, CDCl3) 21.4, 35.7, 50.6, 127.3, 129.6, 134.8, 143.7, 173.5; LRMS (ES+) calcd for [C10H13NO4S+H] 244.06. found 244.07 [M+H].

1. customAll solvents were evaporated, apart from water
2. additionThe remaining aqueous solvent was diluted further
3. washthoroughly washed with ethyl acetate
4. extractionthe product extracted with ethyl acetate
5. dry with materialdried over Na2SO4
6. filtrationfiltered
7. concentrationconcentrated