Patent ID: 6384238
Filing Date: 2002-05-07
Classification: C07D

Abstract:
A process for the preparation of compounds of formula wherein R1 and R2 are independently hydrogen or alkyl with one to three C atoms, R3 and R4 are independently hydrogen or alkyl with one to three C atoms, R5 is hydrogen, halogen or alkyl with one to three C atoms, R6 is a protecting group; which comprises combining of acyl chlorides of the formula â€ƒin the presence of a halide of the formula KXn in which K is Li, Mg, Ca, Zn, Fe or Ni and X is Cl or Br, and n is 1, 2, or 3, depending on the cation charge of K, with an alcohol of formula â€ƒin an organic solvent in the absence of dialkylaminopyridine as a catalyst to yield a compound of formula: