Cobalt‐Catalyzed Multi‐Substituted Alkene Synthesis from 1,3‐Dithiolanes and Grignard Reagents

The cobalt‐catalyzed reaction between 1,3‐dithiolanes and Grignard reagents, for the efficient synthesis of multi‐substituted alkene products, is described. The method was applicable to a variety of benzylic dithiolane substrates, affording di‐, tri‐, and tetra‐substituted 1,1‐diaryl alkene products in good to excellent yields. The use of benzylic Grignard reagents with aryl aldehyde‐derived 1,3‐dithiolanes enabled access to natural product‐derived stilbene architectures with exquisite E selectivity. The operational simplicity, low catalyst loadings, and scalability demonstrate the general utility of the method.