摘要 |
Pharmaceutically useful optically active alpha -arylalkanoic acids of the formula <CHEM> where Ar is aryl and R1 is alkyl or cycloalkyl or esters, ortho esters, or amides thereof are stereoselectively prepared by contacting a reagent of the formula Ar-MX, (Ar) 2M or ArM' where M is Cd, Cu(II), Mn(II), Mg or Zn, and M' is Cu(I) or Li, and X is halogen, with an optically active compound of the formula <CHEM> where Z is a leaving group and Y is halogen, acyloxy or <CHEM> where R' and R'' are alkyl, aryl or with N are a heterocyclic group, to form the optically active ketone of the formula <CHEM> which is ketalized and rearranged to said acid, ester, ortho ester or amide. Alternatively, said ketone is reduced to the corresponding alkanol, which is rearranged to the alpha -arylalkanal. The alkanal so produced is converted to said acid by conventional methods. |