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Updated: Feb 22, 2026
Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
Dynamic Reactivity: Reversible Reaction of a Phosphinine-Borane Adduct With Water and Double Hydrophosphination
Samantha Frank1, Ádám Horváth2, Júlia Boglárka Horváth2
1Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany.
Abstract:
An unprecedented reversible addition of water to a 3,5-bis(SiMe3)phosphinine→B(C6F5)3 was observed, revealing the formation of novel 1,2- and 1,4-dihydrophosphinine oxide-borane adducts. Experimental results, supported by DFT calculations, unveiled two plausible reaction pathways, enabled by the liberation of phosphinine upon water coordination to the borane. On the basis of our results, the water addition can be reversed under basic conditions, regenerating the aromatic phosphorus heterocycle. Furthermore, treating the mixture of the dihydrophosphinine oxides with the sterically demanding and weak base tris(tert-butyl)phosphine induced a unique double hydrophosphination, yielding a bicyclic diphosphine oxide. These findings highlight a new mode of small molecule activation and dynamic structural interconversion by aromatic phosphorus heterocycles.
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