Complementary to C–H
bond activation, C–C bond activation has emerged over the past few years as an
increasingly powerful tool to access and modify complex molecules. Ketones,
owing to their versatility and availability, provide a significant platform for
C–C bond activating reactions. Herein, we reported a <i>β</i>-carbon
elimination strategy for alkene(sp<sup>2</sup>)–C(O) bonds to realize the
olefination of unstrained enones via a vinyl palladium species, which delivers
a series of conjugated polyene compounds. The protocol features broad substrate
scope, excellent functional group tolerance and can be extended to dba
(dibenzylideneacetone) substrates for olefination, alkynylation, arylation and
amination, which demonstrates the generality of the approach and affords two
valuable products in one pot. Furthermore, the late-stage functionalization of
natural products (<i>β</i>-ionone and acetyl cedrene) and synthesis of
natural products (piperine, lignarenone, novenone) highlight the potential
utility of the reaction.