[C:1]([O:4][C:5]1[CH:18]=[CH:17][C:8]([C:9]([CH2:11][C:12]([O:14][CH2:15][CH3:16])=[O:13])=[O:10])=[CH:7][CH:6]=1)(=[O:3])[CH3:2].N.B.Cl>CCOCC>[OH:10][CH:9]([C:8]1[CH:7]=[CH:6][C:5]([O:4][C:1](=[O:3])[CH3:2])=[CH:18][CH:17]=1)[CH2:11][C:12]([O:14][CH2:15][CH3:16])=[O:13]A 250 ml round bottom flask was charged with 11.25 grams (0.045 mol.) of ethyl 4-acetoxy-benzoylacetate and 150 ml of diethyl ether. The solution was stirred and ammonia-borane (1.39 gm., 0.045 mol., Alfa) was added in 4 portions. After being stirred 90 minutes at room temperature 50 ml of ether were added and the reaction mixture was slowly poured into a 400 ml beaker containing 20 ml of 3 N HCl and 100 ml of crushed ice. After 15 minutes the organic phase was separated. The aqueous phase was extracted with ether (2×100 ml). The combined organic phase was washed with brine, dried over magnesium sulfate, filtered and evaporated. The crude product was purified by flash chromatography, using a 7 cm. diameter column of 250 grams silica gel, packed and eluted with 25% ethyl acetate/petroleum ether. 6.53 grams of ethyl 3-hydroxy-3-(4-acetoxyphenyl)propionate was obtained. The product was identical to that obtained by method A as determined by NMR and elemental analysis.
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