반응 #335261

반응 방정식

(+)-4-[[2-(1,1-dimethylethoxy)-2-oxoethyl]oxy]-alpha-methyl-benzenepropanoic acid, methyl ester

→

title compound

수율 93.0%

(+)-4-[[2-(1,1-Dimethylethoxy)-2-oxoethyl]oxy]-alpha-methyl-benzenepropanoic acid

수율 93.0%

용매

phosphate

ethyl ether

반응 조건

후처리

1. 1
   기타Evaporate the solvent in vacuo
2. 2
   기타to leave a white powder
3. 3
   workup.ADDITIONAdd lipase P-30 (5.74 g)
4. 4
   여과Filter
5. 5
   추출extract with ethyl ether (3×400 mL)
6. 6
   건조Dry (MgSO4)
7. 7
   기타evaporate the solvent in vacuo
8. 8
   기타purify by flash chromatography (5→10% methanol/chloroform)

실험 절차

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).

출처