SPECIFIC ALLYLIC-ALLYLIC COUPLING PROCEDURES EFFECTED BY LIGAND-INDUCED ELIMINATION FROM DI(ALLYLIC)PALLADIUM SPECIES

Article abstract of DOI:10.1016/S0040-4020(01)91417-6

Bis(allylic)palladium complexes can be induced to undergo reductive elimination by replacement of phosphine ligands in the system with ?-acidic ligands.The product 1,5-dienes, formed in high yield, are predominantly the 'head-to-head' coupled isomers.The bis(allylic)palladium intermediates may be formed by addition of an allylic Grignard or trialkyl(allylic)tin reagent to an(η³-allyl)palladium chloride complex, or by 1,3-diene condensation.The latter process leads to cyclodimerization, 'unusual' for palladium catalysed reactions.