The Preparation of 2-(1-Phenyl-5-Phenyl or 5-Substituted Phenyl-1H-Pyrazol-3-Yl)Phenols from Trilithiated 2′-Hydroxyacetophenone Phenylhydrazone and Aromatic Esters

Abstract

2′-Hydroxyacetophenone phenylhydrazone was trilithiated with excess lithium diisopropylamide, and the resulting trianion-type intermediate was condensed with a variety of aromatic esters followed by acid cyclization to 2-(l-phenyl-5-phenyl or 5-substituted phenyl-1H-pyrazol-3-yl)phenols.