Alkyne hydroarylation in ionic liquids catalyzed by palladium(II) complexes
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Updated: Jun 11, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Andrea Biffis1, Luca Gazzola, Cristina Tubaro
1Dipartimento di Scienze Chimiche, Università di Padova via F. Marzolo, 1-35131 Padova, Italy. andrea.biffis@unipd.it
Abstract:
The efficiency of dicarbene palladium(II) complexes and of simple palladium(II) acetate as catalysts for alkyne hydroarylation under liquid-liquid biphasic conditions involving an ionic liquid as the catalyst-containing phase is investigated. The results obtained under these conditions, both in terms of activity and selectivity, are compared with those previously obtained under homogeneous conditions. The catalytic efficiency of the systems is found to be markedly dependent on the nature of the anion of the ionic liquid. Suitable anions are found to significantly improve the catalytic performance in comparison to homogeneous conditions. Preliminary investigations on the recyclability of the system as well as the on advantages of using an acidic ionic liquid are also carried out.
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