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Updated: Aug 9, 2026

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
High atom-economical one-pot synthesis of secondary phosphines and their borane complexes using recycling phosphorus
Graziano Baccolini1, Carla Boga, Marzia Mazzacurati
1Dipartimento di Chimica Organica "A. Mangini" Alma Mater Studiorum-Universita' di Bologna, Viale Risorgimento 4, 40136 Bologna, Italy. baccolin@ms.fci.unibo.it
Abstract:
[reaction: see text] A general new method for the one-pot preparation of secondary phosphines 11 and in situ generation of their borane complexes 12 is described. This method consists of the sequential addition, at room temperature, of equivalent amounts of R(1)MgBr and R(2)MgBr to 1 equiv of the phosphorus atom donor reagent 1. Final treatment with water gives secondary phosphines R(1)R(2)PH (or the corresponding phosphine-borane complexes if treated with BH(3).THF) and the end product 6, which can be recycled.
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