Deprotonation of a chiral alpha-oxygenated nitrile with the base 2,2,6,6-tetramethylpiperidylmagnesiumchloride, TMPMgCl, gives rise to a chiral magnesiated nitrile, and thisanion has sufficient configurational stability at low temperature to allow the formation ofhighly enantiomerically enriched substituted nitrile products after electrophilic quench.
Alshawish, M., Barker, G., Measom, N. D., & Coldham, I. (2017). Metalation-Substitution of an α-Oxygenated Chrial Nitrile. Comptes Rendus Chimie, 20(6), 601-608. https://doi.org/10.1016/j.crci.2016.11.006