Synthesis of alkyl-H-phosphinic acid alkyl esters from red phosphorus and alkyl bromides

Alkyl-H-phosphinic acid alkyl esters are synthesized in 65–71% yield via chemoselective reaction of alkyl bromides with available alkyl-H-phosphinic acids (60–65 °C, Et3N). The latter are prepared, in turn, by direct phosphorylation of alkyl bromides with red phosphorus under phase-transfer conditions.