A map of nucleophilic substitution at silicon in solution

Abstract

The course of nucleophilic substitution at silicon involving a pentacoordinate intermediate is mapped in solution;¹ the method involves correlating the extent of nucleophile–silicon bond-making (as determined by the pyridone ring carbon chemical shifts) with the coordination state of the silicon (as inferred from the ²⁹ Si NMR chemical shifts); the reaction under study is the displacement of X (X = OR, F, Cl, Br, OSO₂CF₃) by oxygen in an intramolecular reaction of a series of N-dimethylsilylmethyl pyridones.