Intramolecular Formal anti‐Carbopalladation/Heck Reaction: Facile Domino Access to Carbo‐ and Heterooligocyclic Dienes

An intramolecular domino process consisting of a formal anti‐carbopalladation followed by Heck reaction is realized. Complex oligo(hetero)cyclic scaffolds are efficiently obtained in one synthetic step from easily obtainable enyne precursors. In contrast to common syn‐carbopalladation reactions of alkyne units, the carbopalladation employed here is designed to afford an anti‐arrangement of the two new substituents across the emerging double bond. A prerequisite is that the residues next to the alkyne should lack any β‐hydrogen atoms. The method paves the way to tri‐ and tetrasubstituted double‐bond systems that have not been accessible by conventional Pd catalysis.