METHOD OF PREPARING 4-HALOGENATED QUINOLINE INTERMEDIATES

摘要

This invention is directed to methods of preparing compounds of formula (I): comprising the step of reacting a compound of formula (II): with a reagent of formula POX₃ and silica gel at a temperature greater than about 75°C, and wherein substitutions at X, PG, A, G, R₁ and R₄ are set forth in the specification.