METHOD OF PREPARING HYDROXY-SUBSTITUTED AROMATIC HETERO-COMPOUNDS

摘要

The invention concerns a method of preparing 5-hydroxypyrimidines, 3-, 4- and 5-hydroxypyridines and 4- and 5-hydroxypyridazines from 5-halopyrimidines, 3-, 4- and 5-halopyridines and 4- and 5-halopyridazines. The method is characterized in that the halo-compound is reacted with a metal hydroxide in an inert solvent at atmospheric pressure in the presence of catalytic amounts of sulphur. The reaction takes place both stereoselectively and chemoselectively and gives high yields. No side products (in particular the product in which the halogen atom is replaced by hydrogen) are produced.