Synthesis of pharmaceutically useful pyridine derivatives

摘要

A process is provided for the preparation of compounds of formula I, useful in the preparation of compounds such as Omeprazole, Lansoprazole and Pantoprazole, wherein R1=H or CH3, R2=H or CH3, R3=Alkoxy (1-4C), OCH2CF3, Cyano, Hydrogen, Halogen, Acetoxy or Aryloxy, any electron withdrawing group or salts (organic or inorganic) of electron donating groups, R=Alkoxy, Hydroxy, Halogen, Activated ester, Tosylate, Mesylate, Thiol or Xanthyl, wherein the process for the preparation of compound of formula I employs a free radical reaction to functionalize the 2-position.