Bis(pentafluorophenyl)phosphinous acid in the synthesis of P,P-bis(pentafluorophenyl)phosphorylalkanones and -alkanediones

Abstract

Addition of bis(pentafluorophenyl)phosphinous acid to , alkenones and ,,´ alkene diones in anhydrous Et 2 O (the solvent, in which the P-OH tautomeric form predominates) proceeds rapidly and regiospecifically at the C=C bond of the substrate at room temperature in the absence of catalysts. The reaction leads to bis(pentafluorophenyl)phosphorylated alkanones and alkanediones, as a rule, in the yields close to quantitative and can be considered as a highly efficient method for the synthesis of the corresponding functionalized phosphine oxides. The structures of obtained compounds were established by IR and NMR spectroscopy and X ray diffraction analysis.