Synthesis of Phosphinoboranes via Coordination-Induced Bromine Abstraction of an Isolable Phosphinyl Radical with Bromoboranes

Abstract

A stable dialkylphosphinyl radical reacted with bromoboranes to afford the corresponding phosphinoboranes accompanied with a bromophosphine under neutral condition at room temperature. The obtained phosphinoboranes have almost planar structures and have an effective P–B dative π-bond. The formation of phosphinoboranes would proceed via coordination-induced bromine abstraction from bromoboranes as a pivotal step, which was supported by the computational study.

Metal-catalyzed valence isomerization of a methylene(thioxo)phosphorane to a thiaphosphirane

“…The PQC bond is not elongated by sulfurization: the double bond length is comparable with the PQC1 bond length in the structurally similar phosphaalkene 4 0 [1.674(2) Å] that has SiMe 3 groups instead of SiMe 2 Ph groups of 4. 21 The PQS bond length of 3 [1.9334(4) Å] is also 9% shorter than the P-S single bond of thiaphosphirane 5 [2.1175(4) Å], which is accord with the theoretically suggested partial PQS double bond character. The C1 and P1 atoms in 3 adopt three trigonal planar geometry [the angle sums of P: 359.98(5)1 and C1: 359.58( 8)1] as well as reported methylene(thioxo)phosphoranes.…”