abstract |
Pharmaceutically useful optically active α-arylalkanoic acids or esters, ortho esters, or amides thereof are stereoselectively prepared by contacting an aryl magnesium Grignard reagent with an optically active α-substituted acyl halide to form the optically active aryl α-substituted alkyl ketone, which is ketalized and rearranged to the desired optically active α-arylalkanoic acid or the corresponding ester, ortho ester or amide. In an alternate embodiment, the aryl α-substituted alkyl ketone is reduced to the corresponding alkanol, which is rearranged to the α-arylalkanal. The alkanal so produced is converted to the desired optically active α-arylalkanoic acid by conventional methods. |