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The activation of CÀH bonds of alkanes remains a major challenge for chemistry. In a series of deuteration experiments with D 2 in contact with bis-(diphenylphosphino) butane (dppb) stabilized ruthenium nanoparticles (liquid substrates, 60 8C, 6 bar D 2 ) we have observed a surprisingly large reactivity of cyclopentane as compared to cyclohexane and other alkanes. DFT calculations using a ligand-free Ru 13 H 17 model cluster as catalyst indicate oxidative CÀH cleavage of the bound substrates as rate limiting reaction step. They also indicate similar binding and activation enthalpies of reactions of cyclopentane and cyclohexane.

The reactions of three metal nanoparticle (MNP) systems Ru/ dppb, RuPt/dppb, Pt/dppb (dppb = 1,4-bis(diphenylphosphino)butane) with gaseous D 2 at room temperature and different gas pressures have been studied using 1 H gas phase NMR, GC-MS and solid state 13 C and 31 P MAS NMR. The main product is gaseous HD arising from the reaction of D 2 with surface hydrogen sites created during the synthesis of the nanoparticles. In a side reaction, some of the dppb ligands are decomposed producing surface phosphorus species and gaseous partially deuterated butane and cyclohexane. These findings are fundamental for detailed studies of the reaction kinetics of these particles towards H 2 or D 2 gas.

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