反应详情

Dissolve (+)-4-[[2-(1,1-dimethylethoxy)-2-oxoethyl]oxy]-alpha-methyl-benzenepropanoic acid, methyl ester (5.74 g, 18.6 mmol) in ethyl ether and adsorb onto silica gel (18 g). Evaporate the solvent in vacuo to leave a white powder. Suspend the powder in pH 7 phosphate buffer (600 mL of a 0.1M solution). Add lipase P-30 (5.74 g) and stir for 16 hours. Filter and extract with ethyl ether (3×400 mL). Dry (MgSO4), evaporate the solvent in vacuo and purify by flash chromatography (5→10% methanol/chloroform) to give the title compound (5.09 g, 98% ee after reesterification with diazomethane); [α]d 20 =+18.9° (C=0.97, CHCl3).

1. customEvaporate the solvent in vacuo
2. customto leave a white powder
3. additionAdd lipase P-30 (5.74 g)
4. filtrationFilter
5. extractionextract with ethyl ether (3×400 mL)
6. dry with materialDry (MgSO4)
7. customevaporate the solvent in vacuo
8. custompurify by flash chromatography (5→10% methanol/chloroform)