| Abstract
| - Diallyl 2-alkyl-2-arylmalonates underwent palladium-catalyzed decarboxylative allylation quickly undermild conditions. In contrast, no reaction took place with diallyl 2,2-dialkylmalonates under the sameconditions. Electron-donating phosphine ligands were found to be vital for this reaction. Most of thesolvents used did not affect the catalytic cycle. Catalysis in [bmim][BF4], a well-known ionic liquid, wasinhibited as a result of formation of a hydrogen bond between a carboxylate anion and a [bmim]+ cation;however, the reaction in [bdmim][BF4], in which the acidic proton of [bmim][BF4] was replaced with amethyl group, proceeded smoothly. The catalytic mechanism was investigated using a tetradeuteratedsubstrate and an enzymatically synthesized enantio-enriched allyl methyl 2-methyl-2-phenylmalonate.Even the electron-deficient phosphite ligand was found to be active for catalysis of diallyl 2-methyl-2-(2- or 4-nitrophenyl)malonates.
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