Toluene

Reagents (Mo(CO)₆, 1H-1,2,3-triazole (97%, Manchester Organics, Runcorn, UK), 1H-1,2,4-triazole (98%), 5–6 M tert-butyl hydroperoxide in decane, anhydrous dichloromethane, toluene (99.9%), acetone (99.5%), diethyl ether (99.8%) and pentane (≥95%, Carlo Erba, Milan, Italy) were purchased from Sigma-Aldrich (St. Louis, MO, USA) unless otherwise indicated. For the catalytic experiments, cis-cyclooctene (95%), acetonitrile (≥99.9%), anhydrous α,α,α-trifluorotoluene (99%), pentane (≥99.5%) and 30% aq. H₂O₂ were acquired from Sigma-Aldrich and used as received. The hybrid metal oxide-triazole material [MoO₃(1,2,4-trz)_0.5] (4) was prepared by the hydrothermal reaction of MoO₃, 1,2,4-trz and water at 180 °C for 1 h [13 (link)]. The phase purity of the microcrystalline product was verified by a comparison of its powder X-ray diffraction (PXRD) pattern with a simulated pattern calculated using the crystal structure data published for 4 (Figure S4 in the Supporting Information) [13 (link)]. The trinuclear complex (1,2,4-Htrz)₂[Mo₃O₆(O₂)₄(1,2,4-trz)₂]⋅H₂O (6) was prepared as described previously by the addition of 1,2,4-trz to the solution obtained upon reaction of MoO₃ with a large excess of H₂O₂ [26 (link)].