Facile activation of homoatomic σ bonds in white phosphorus and diborane by a diboraallene

Abstract

Metal‐free activation of homoatomic E−E σ bonds (E=P, B) in white phosphorus (P4) and bis(catecholato)diboron (B2cat2) with a 1,2‐diboraallene 1 is reported. The 1:1 and 1:2 reactions of P4 with 1 afford BnP4 cages (2: n=2, 3: n=4), whereas a stoichiometric mixture of 1 and B2cat2 undergoes homonuclear catenation through the addition of the B−B σ bond of B2cat2 across the B=B double bond of 1 (i.e. diboration), which leads to the formation of a tetraborane (4) featuring a B4 chain.