H-phosphonate mediated sulfonylation of 2-substituted quinoline N-oxides: One-pot strategy for the synthesis of 3/4-sulfonylquinoline derivatives

Abstract

GRAPHICAL ABSTRACT ABSTRACT A series of biologically important 3/4-sulfonylquinoline derivatives was synthesized starting from easily available sodium benzenesulfinates, diethyl H-phosphonate and 2-substituted quinoline N-oxides in one-pot under metal-free conditions. H-phosphonate plays a decisive role in activating the C3-H, C4-H bonds of the 2-substituted quinoline N-oxides. The isolated 3/4-sulfonylquinolines were characterized by 1H, 13C NMR spectroscopy and HR MS.