Hydrogen tunneling in protonolysis of platinum(II) and palladium(II) methyl complexes: mechanistic implications.

J Am Chem Soc

Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology, Pasadena, California 91125, USA.

Published: December 2008


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Article Abstract

Platinum(II) and palladium(II) complexes are well-known to catalyze the partial oxidation of alkanes. Herein, we present experimental evidence that tunneling occurs in the protonolysis of M(II)-CH(3) (M = Pt, Pd) model systems. We propose that there may be a connection between the observation of tunneling and a protonolysis mechanism involving direct protonation of the M-C bond and that tunneling may also be expected for electrophilic C-H activation of methane by Pt(II) and Pd(II) that proceeds via direct proton loss from a sigma complex.

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Platinum(II) and palladium(II) complexes are well-known to catalyze the partial oxidation of alkanes. Herein, we present experimental evidence that tunneling occurs in the protonolysis of M(II)-CH(3) (M = Pt, Pd) model systems. We propose that there may be a connection between the observation of tunneling and a protonolysis mechanism involving direct protonation of the M-C bond and that tunneling may also be expected for electrophilic C-H activation of methane by Pt(II) and Pd(II) that proceeds via direct proton loss from a sigma complex.

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