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Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
Solvent-induced stereochemical behavior of a bile acid-based biphenyl phosphite: a computational study
Antonella Cimoli1, Giacomo Prampolini, Alessandro Tani
1Dipartimento di Chimica e Chimica Industriale, Università di Pisa, via Risorgimento 35, I-56126 Pisa, Italy.
Abstract:
The origin of the stereochemical behavior experimentally found in a bile acid-derived biphenyl phosphite is studied by means of quantum mechanical methods. The molecular mechanisms driving the screw sense of the dihedral angle between the two phenyl rings of the biphenyl phosphite unit are investigated with density functional theory calculations. Energy, geometry, and circular dichroism spectra have been computed and compared between the two resulting diastereoisomers. We evaluated the solvent effect on the torsional energy profile by discussing the results obtained for the isolated molecule with those found with polarizable continuum model (PCM) calculations performed in different solvents. The results we obtain with the PCM model do not reproduce the solvent effect on the stereochemical equilibrium of this phosphite.
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