Stereospecific reduction of phosphine oxides to phosphines by the use of a methylation reagent and lithium aluminum hydride.

[figure: see text] Various phosphine oxides are efficiently reduced by the use of a methylation reagent and lithium aluminum hydride. Optically active P-chirogenic phosphine oxides are also reduced with inversion of configuration at phosphorus atom by treatment with methyl triflate, followed by reaction with LiAlH4.