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Updated: Oct 14, 2025

A Protocol for Safe Lithiation Reactions Using Organolithium Reagents
Published on: November 12, 2016
Racemization mechanism of lithium tert-butylphenylphosphido-borane: A kinetic insight
Rémy Fortrie1, David Gatineau2, Damien Hérault1
1Aix Marseille Univ, CNRS, Centrale Marseille, iSm2, Marseille, France.
Abstract:
The racemization mechanism of tert-butylphenylphosphido-borane is investigated experimentally and theoretically. Based on this converging approach, it is shown, first, that several phosphido-borane molecular species coexist at the time of the reaction and, second, that one particular of both initially assumed reactive routes most significantly contribute to the overall racemization process. From our converging modeling and experimental measurement, it comes out that the most probable species to be here encountered is a phosphido-borane-Li (THF)2 neutral solvate, whose P-stereogenic center monomolecular inversion through a Y-shaped transition structure (Δr G°≠ : 81 kJ mol-1 ) brings the largest contribution to the racemization process.
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