A bis(silylene)-stabilized diphosphorus compound and its reactivity as a monophosphorus anion transfer reagent

In contrast to the well-established transition-metal-mediated activation of white phosphorus (P₄), the metal-free direct functionalization of P₄ has remained rare. The conversion of P₄ into a reactive zero-valent diphosphorus compound (P₂) has proven challenging to carry out without relying on metal reactivity. Herein, we describe the facile degradation of P₄ mediated by two divalent silicon atoms in a bis(silylene) scaffold, resulting in a silylene-stabilized zero-valent P₂ complex. The presence of two lone pairs of electrons on each P atom in the silylene-stabilized P₂ complex enables a rich reactivity towards small molecules; reaction of the P₂ species with CO₂, water or a borane leads to the formation of P-C, P-H or P-B bonds, respectively. Notably, the P₂ complex also serves as a single phosphorus anion (P^-) transfer reagent towards metal carbonyls and a chlorogermylene compound, leading to the synthetically valuable phosphaketenide (PCO^-) ligand and a phosphinidene germylene complex, respectively.