反应详情

A solution of 0.10 mole (1 eq.) of α,α-dimethylphenylacetic acid methyl ester 2 in 150 mL of MeOH and 50 mL of water was added 1.02 mole (10. 1 eq.) of KOH pellets. After stirring at room temperature for 3.5 days, the methanol was stripped off by rotary evaporation. To the residual liquid was added 100 mL of water and enough concentrated HCl to bring to ˜pH 3. The aqueous solution was extracted with Et2O (3×100 mL). The combined organic layers were dried over MgSO4 and vacuum filtered. The filtrate was rotary evaporated and dried under vacuum to give a white solid as α,α-dimethylphenylacetic acid 3 (87-89%). Method D

1. customthe methanol was stripped off by rotary evaporation
2. additionTo the residual liquid was added 100 mL of water and enough concentrated HCl
3. extractionThe aqueous solution was extracted with Et2O (3×100 mL)
4. dry with materialThe combined organic layers were dried over MgSO4 and vacuum
5. filtrationfiltered
6. customThe filtrate was rotary evaporated
7. customdried under vacuum