The synthesis of (E)-arylidene and allylidene cyclopentanes by means of a pallodium(0)-catalyzed complex

Article abstract of DOI:10.1016/S0040-4020(01)86561-3

When treated with an unsaturated halide in a palladium-catalyzed process, the anions from γ-acetylenic malonates 4 and 5 stereospecifically lead to cyclopentanes having an exo tri- or tetra-substituted double bond. This reaction which forms simultaneously two carbon-carbon bonds is believed to proceed by nucleophilic attack of the anion on the triple bond activated by the σ-aryl or σ-vinyl palladium complex.