Palladium-catalyzed allylic alkylation with a variety of active methylene compounds has been carried out in the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]). Phosphine ligands are found to exert a profound effect on the active palladium species, with the more electron-donating ones such as PCy3 affording faster rates and the strong electron acceptors such as P(OPh)3 affording extremely low conversions. In the most commonly used molecular solvent, THF, the reaction is slower and the choice of ligands is more limited. These observations may be accounted for by the allylpalladium intermediate existing in different forms in the two solvents.

Palladium-catalyzed allylic alkylation with a variety of active methylene compounds has been carried out in the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]). Phosphine ligands are found to exert a profound effect on the active palladium species, with the more electron-donating ones such as PCy3 affording faster rates and the strong electron acceptors such as P(OPh)3 affording extremely low conversions. In the most commonly used molecular solvent, THF, the reaction is slower and the choice of ligands is more limited. These observations may be accounted for by the allylpalladium intermediate existing in different forms in the two solvents.

[figure: see text] Palladium-catalyzed arylation of the electron-rich olefin butyl vinyl ether has been accomplished in the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]), using as the arylating agents aryl iodides and bromides instead of the commonly used, but commercially unavailable and expensive, aryl triflates. The reaction proceeds with high efficiency and remarkable regioselectivity, leading almost exclusively to substitution by various aryl groups at the olefinic carbon alpha to the heteroatom of butyl vinyl ether.