TY - JOUR

T1 - Suzuki-Miyaura coupling reactions using novel metal oxide supported ionic palladium catalysts

AU - Lichtenegger, Georg J.

AU - Maier, Manuel C.

AU - Hackl, Markus

AU - Khinast, Johannes G.

AU - Gössler, Walter

AU - Grießer, Thomas

AU - Phani Kumar, V.S.

AU - Gruber-Woelfler, Heidrun

AU - Deshpande, Parag Arvind

PY - 2017

Y1 - 2017

N2 - Palladium substituted CeO2, SnO2 and their mixed oxides have been synthesized in quantitative yields out of non-toxic and inexpensive precursors using a simple and rapid single step solution combustion method. The resulting oxides, especially the mixed oxides Ce0.79Sn0.20Pd0.01O2-δ, Sn0.79Ce0.20Pd0.01O2-δ and Sn0.99Pd0.01O2-δ proved to be highly active (TOF > 12,000 h−1) for Suzuki-Miyaura cross-couplings of phenylboronic acid with various bromoarenes. The reactions were carried out in ambient air at moderate temperatures using environmentally friendly aqueous ethanol solutions as reaction solvents. Minimal amounts of palladium in the product solution ( < 0.14 mg/L), the reaction kinetics as well as catalyst poisoning tests support the thesis that the reaction proceeds via dissolved palladium species in a homogeneous reaction mechanism. Nevertheless, the synthesized catalysts could be reused for at least five times with only minor changes in activity and no changes in the crystal structure, indicating the high potential of the investigated catalysts as quasi-heterogeneous Csingle bondC coupling catalysts.

AB - Palladium substituted CeO2, SnO2 and their mixed oxides have been synthesized in quantitative yields out of non-toxic and inexpensive precursors using a simple and rapid single step solution combustion method. The resulting oxides, especially the mixed oxides Ce0.79Sn0.20Pd0.01O2-δ, Sn0.79Ce0.20Pd0.01O2-δ and Sn0.99Pd0.01O2-δ proved to be highly active (TOF > 12,000 h−1) for Suzuki-Miyaura cross-couplings of phenylboronic acid with various bromoarenes. The reactions were carried out in ambient air at moderate temperatures using environmentally friendly aqueous ethanol solutions as reaction solvents. Minimal amounts of palladium in the product solution ( < 0.14 mg/L), the reaction kinetics as well as catalyst poisoning tests support the thesis that the reaction proceeds via dissolved palladium species in a homogeneous reaction mechanism. Nevertheless, the synthesized catalysts could be reused for at least five times with only minor changes in activity and no changes in the crystal structure, indicating the high potential of the investigated catalysts as quasi-heterogeneous Csingle bondC coupling catalysts.

U2 - 10.1016/j.molcata.2016.10.033

DO - 10.1016/j.molcata.2016.10.033

M3 - Article

VL - 426.2017

SP - 39

EP - 51

JO - Journal of molecular catalysis / A

JF - Journal of molecular catalysis / A

SN - 1381-1169

IS - 39

ER -