A Remarkable Catalyst-Free Photochemical Alkene Hydrophosphination with Bis(trimethylsilyl)phosphonite

This publication delves into a comprehensive exploration of a new synthetic route to functionalized phosphorus-derived compounds. Bis(trimethylsilyl)phosphonite HP(OSiMe₃)₂, prepared in a high yield from H₃PO₂, was found to be an excellent reagent for hydrophosphination of activated, unactivated, and amino acid-derived olefins under UV irradiation and catalyst-, solvent- and glovebox-free conditions. The resulting phosphorus trivalent compounds have been subjected to postfunctionalization, leading to the formation of H-phosphinate, phosphonate, and thiophosphonate end products in good to excellent yields. With a combination of experimental and theoretical calculations, the mechanism for this hydrophosphination reaction has been investigated, revealing a radical process.