Ene-Yne Metathesis

Ene-yne metathesis (EYM) is an efficient catalytic method for diene synthesis using simple unsaturated reactants. The reaction shows excellent functional group tolerance characteristic of the Grubbs ruthenium carbenes. That the ruthenium carbenes are widely available and easy to use explains the widespread application of EYM in organic chemistry. Successful ring-closing applications have led to increased use of EYM in total synthesis. Some of the synthetic appeal is due to the accessibility of the simple reactants and the use of the resulting 1,3-dienes in subsequent transformation including cascade reactions. Combined metathesis sequences or tandem reactions provide a rapid gain in structural complexity using a catalytic reaction as the key carbon-carbon bond-forming step. The successful application of EYM in complex molecule synthesis combined with continuing improvements in substrate scope and a refined understanding of reaction mechanism has made EYM a useful synthetic method for C-C bond construction. This chapter reviews the literature of EYM and provides an overview of the reactions' capabilities.