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Updated: May 2, 2026

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Mechanistic insights on the stereoselective nucleophilic 1,2-addition to sulfinyl imines
Martin Hennum1, Heike Fliegl, Lise-Lotte Gundersen
1Department of Chemistry, University of Oslo , P.O. Box 1033, Blindern, N-0315 Oslo, Norway.
Abstract:
The asymmetric nucleophilic 1,2-addition of (S)-N-benzylidene-2-methylpropane-2-sulfinamide with methylmagnesium bromide and methyllithium has been investigated using DFT(B3LYP) computations. The calculated ratio of the two diastereomers agrees with experimental observations, and the factors that determine the diastereomeric ratio are discussed. The preference for the E isomer and the rapid equilibrium between the E and Z isomers of N-tert-butanesulfinyl imine are two key features for understanding the mechanism of this reaction. Methylmagnesium bromide and methyllithium have bifunctional roles, acting as both Lewis acid and nucleophile, and the Lewis acid character plays a determining role in the stereoselectivity of the reaction.
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