A Novel Type of Dyotropic Rearrangement. Palladium-Catalyzed Rearrangement of Alkoxymethyl-Substituted Silanes to Alkyl Silyl Ethers

Abstract

The treatment of alkoxymethyl-substituted hydrosilanes with palladium on charcoal gave rise to the corresponding alkyl silyl ethers by the migration of the silicon-bound hydrogen atom to the a-carbon atom and of the alkoxy group to the silicon center. Kinetic investigations revealed that two parallel reactions are involved in the rearrangement: an intramolecular reaction, following pseudo-first-order kinetics and showing an inverse kinetic deuterium isotope effect, is dominant in the initial phase of the transformation, and an intermolecular reaction becomes important in the later course of the transformation. The dominant reaction in the first phase of the transformation has to be classified as a dyotropic arrangement of type I, due to the intramolecular course and the reaction order, and it represents the first catalyzed example of a rearrangement of this type.