The catalytic cleavage under hydrogen of the C-H and C-C bonds of alkanes with conventional catalysts requires high temperatures. Room-temperature hydrogenolysis of simple alkanes is possible on a well-defined and well-characterized zirconium hydride supported on silica obtained by surface organometallic chemistry. The surface structure resulting from hydrogenolysis of (≡SiO)Zr(Np) 3 (Np, neopentyl) was determined from the extended x-ray absorption fine structure (EXAFS) and 1 H and 29 Si solid-state nuclear magnetic resonance and infrared (IR) spectra. A mechanism for the formation of (≡SiO) 3 Zr-H and (≡SiO) 2 SiH 2 and the resulting low-temperature hydrogenolysis of alkanes is proposed. The mechanism may have implications for the catalytic formation of methane, ethane, and lower alkanes in natural gas.

At 50°C already the hydrogenolysis of neopentane, isobutane, and propane is catalyzed by the silica‐supported zirconium hydride [( ⦠ SiO)3ZrH]. The reaction selectively produces methane together with isobutane, propane, and ethane, respectively. The activity is attributable to the high electrophilicity of the 8‐electron do complex and is not observed for nonsupported, discrete zirconium hydrides. Moreover, the attachment to the support prevents a bimolecular deactivation.

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