Efficient and Mild C-H Alkenylation of Heteroarenes Activated by Thioether-Coordinated Palladium Catalyst

Abstract

Cross Dehydrogenative Coupling is a green and more efficient synthetic technique than traditional coupling chemistry because there is no prefunctionalization step. Ancillary ligands using simple sulfur ligands can increase the Pd catalyst yields comparable to inexpensive Phosphate ligands, which are not oxidatively stable. Thioether ligands are oxidatevly stable and odorless and have been shown to function under mild conditions. Select thioether ligands can activate electron rich alkenes and activate non-thermodynamically favored arene sites. In addition, methionine is a viable thioether ligand target opening the possibility for protein and amino acid based Pd catalysis.