A variety of homoleptic and heteroleptic, triply bonded dimolybdenum hexaalkoxides, [(Mo2(OR)6] and [Mo2(OR)4(OR′)2], were successfully applied as dual pre‐catalysts in both, the epoxidation of olefins with tert‐butyl hydroperoxide and the deoxygenation of diorganosulfoxides with silanes, to form the corresponding sulfides. In the epoxidation of cyclooctene, the pre‐catalysts demonstrated an intriguingly high activity, with turnover frequencies (TOFs) of above 60 000 h−1 at elevated temperatures (≈50 °C) and even very high activity at room temperature. Furthermore, using [Mo2(OtBu)6] as a pre‐catalyst, we studied the effect of the solvent and we extended the epoxidation reaction to more demanding olefins, which revealed a particularly high activity even towards primary alkenes. In addition, the same pre‐catalysts, in comparison to previously reported Mo‐based systems, exhibited excellent activities for the deoxygenation of phenyl methyl sulfoxide to thioanisole in the presence of silanes (TOFs>160 h−1). A number of other diorganosulfoxides were used in the catalytic deoxygenation to investigate the scope and limitations of the system, displaying an excellent performance for differently substituted substrates.

The formamidines ArNHC(H)=N–Ar [Ar = Ph (2a), 4‐F‐Ph (2b), 3,5‐F2Ph (2c) and 2,6‐F2Ph (2d) and R = 2,3,5‐F3Ph (2e), 3,4,5‐F3Ph (2f), F5Ph (2g) and 4‐CF3Ph (2h)] were synthesized and the influence of the introduction of a fluorine or a trifluoromethyl group into the aryl unit on the solid‐state structures was investigated. On comparing the experimental data, only marginal differences in the geometrical and electronic features of the diverse substituted species were detected. DFT calculations and X‐ray crystallography of 2d–2g revealed that the E‐syn‐configuration corresponded to the thermodynamically most stable motif of all of the examined formamidines. However, in their solid‐state, these ligands showed a range of H···F interactions, which varied depending on the number and position of the fluorine atoms on the aryl group and thus led to interesting solid‐state structures. Moreover, compounds 2 were used for the synthesis of the new heteroleptic dimolybdenum triply‐bonded complexes, Mo2[(2a–2c; 2e–f)–H]2(OtBu)4 (3a–3c; 3e–3f). X‐ray crystallography of complexes 3c and 3f revealed two different isomers in the solid state: in trans‐3c the two formamidines are in one plane, while in cis‐3c and cis‐3f they are next to each other. The DFT calculations showed only a small distinction in energy between the configurations, which led us to assume that the different configurations were induced by the crystal packing. The specific H···F interactions provided by the different formamidines led to a two‐dimensional arrangement for trans‐3c and a three‐dimensional network for cis‐3c and cis‐3f.

Triple bonds do it! The molybdenum‐catalyzed CN bond cleavage of organic amides with hydrosilanes to produce alcohols and amines has been investigated. This work complements previously established protocols that lead to the cleavage of the CO bond. Modified triply bonded dimolybdenum(III) alkoxides have been found to be crucial for tuning the selectivity to CN bond cleavage (see figure).

A series of monodentate, triply bonded Mo 2 (OR) 6 complexes [R = MBE (1) (MBE = 2-methylbut-3-ene-2-yl), MMP (2) (MMP = 1-methoxy-2-methylpropane-2-yl), Terp (3) [Terp = 2-(4-methylcyclohex-3-enyl)propane-2-yl], which exhibit C-C double bonds or an ether function in the ligand sphere, were synthesized and characterized by multinuclear ( 1 H, 13 C and 95 Mo) NMR studies. The partial alcoholysis of the latter complexes with neopentyl alcohol (neopentOH) led to the heteroleptic alkoxides Mo 2 (OR) n (Oneopent) 6-n (4-7) {n = 2 [for R = tBu (4), MBE (5), MMP (6)], 4 [for R = Terp (7)]}. This concept was further applied to the synthesis of Mo 2 (O 2 DMH) 2 -(OtBu) 2 (8) (DMH = 2,5 dimethylhexyl) by starting from the Mo 2 (OtBu) 6 precursor. The 1 H NMR spectra for the heteroleptic complexes 4-8 show signals that are significantly shifted to a higher field for the RO ligand protons compared to those of their homoleptic analogues. This is the result of a change in the spatial position of the alkoxide ligands (RO) in the homoleptic compared to the heteroleptic complexes that

The general method of doping metals with organic, bio‐organic, and polymeric dopants is extended to inorganic dopants. Specifically, the heteropolyacids H3[P(M3O10)4] (PMA; M=Mo, W) were successfully entrapped within a metallic silver matrix. The obtained PMA@Ag composites were fully characterized by PXRD, surface area, SEM, TEM and EDX measurements, showing a homogenous distribution of the catalyst in the support. The new composite materials are successfully applied in the catalytic alkylation of arenes, as demonstrated by the successful adamantylation of toluene or anisole with 1‐bromoadamantane. Furthermore, this reaction is applied with the less reactive 1‐chloroadamantane in both the supported and unsupported case. PMoA, which easily decomposes under the applied reaction conditions, is protected by entrapment and shows increased activity when supported in the silver matrix. In the same reaction, the entrapped PWA shows a drastically increased reaction rate compared to the free acid, which further confirms the positive synergistic effects of the entrapment process. Both heterogenized catalysts are successfully recycled and reused, but the reaction time steadily increases in successive cycles due to agglomeration of the catalyst, which results in a lower accessibility of the dopant. Moreover, the alkylation can be extended to other alkyl chloride substrates, as demonstrated for tert‐butyl chloride.