Metallacycle-Mediated Cross-Coupling with Substituted and Electronically Unactivated Alkenes.

This perspective surveys the history of- and recent advances in- metallacycle-mediated coupling chemistry of substituted alkenes. While the reaction of preformed metal-π complexes with ethylene was reported nearly 30 years ago, the generalization of this mode of bimolecular C-C bond formation to the regio- and stereoselective union of complex substrates has only recently begun to emerge. This perspective discusses early observations in this area, the challenges associated with controlling such processes, the evolution of a general strategy to overcome these challenges, and a summary of highly regio- and stereoselective convergent coupling reactions that are currently available by metallacycle-mediated cross-coupling with substituted alkenes.