α-Tertiary Dialkyl Ether Synthesis via Reductive Photocatalytic α-Functionalization of Alkyl Enol Ethers
Jamie A. Leitch, Thomas Rossolini, Tatiana Rogova, Darren J. Dixon
Abstract
The photocatalytic construction of C(sp3)-rich α-tertiary dialkyl ethers through the reductive α-functionalization of alkyl enol ether substrates with conjugated alkenes in the presence of a Hantzsch ester terminal reductant under blue LED irradiation is described. Pivoting on oxocarbenium ion generation via an initial TMSCl-facilitated protic activation of the enol ether substrate, subsequent single-electron transfer to this intermediate delivers the putative nucleophilic α-oxy tertiary radical capable of productively combining with a variety of alkene substrates. The reductive functionalization strategy was simple to perform, efficient, broad in scope with respect to both alkene acceptor and enol ether donor fragments, and delivered a wide range of complex α-tertiary dialkyl ether architectures.