N,N,N′,N′-TETRAMETHYLCHLOROFORMAMIDINIUM CHLORIDE AS AN EFFICIENT CONDENSATION REAGENT FOR A NOVEL ESTERIFICATION APPLICABLE TO THE MACROLIDE SYNTHESIS

Abstract N,N,N′,N′-Tetramethylchloroformamidinium chloride, prepared easily from N,N,N′,N′-tetramethylurea and oxalyl chloride, is found to be an efficient condensation reagent for an esterification of carboxylic acids with alcohols under mild conditions in one-pot procedure, and the reagent is applied to the lactonization for macrolide synthesis from ω-hydroxycarboxylic acids.