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For the first time, microwave (MW) irradiation was successfully applied to peroxidative cyclohexane oxidation catalyzed by a C-scorpionate complex, [FeCl 2 (Tpm)] (1; Tpm = hydrotris-(pyrazol-1-yl)methane), providing a highly selective and fast ecofriendly procedure to produce a KA (cyclohexanol + cyclohexanone) oil mixture (up to ca. 100% selectivity) with 28% yield in 1 h at 50 °C in MeCN. Water, organics, and ionic liquids (ILs, [bmim][N(CN) 2 ] and [bmim][BF 4 ]) were used as solvents, and their interactions with 1 were determined by DFT calculations. The possibility to recycle and reuse 1 (up to nine consecutive cycles) without loss of activity is also observed for the IL [bmim][BF 4 ]. Moreover, higher catalytic activities under additive-free conditions are obtained with the ILs in comparison to those with the other solvents. Tuning the alcohol/ ketone selectivity is also possible by choosing the appropriate IL solvent.

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The cationic isocyanide alkenyl-carbyne complexes [dppe = κ 2-(P,P)-Ph2P(CH2)2PPh2; R = Bun, n = 1 (2a); R = But, n = 1 (2b), 4 (2c); R = Cy, n = 1 (2d), 4 (2e); R = PhCH2, n = 1 (2f), 4 (2g); R = 2,6-Me2C6H3, n = 1 (2h), 4 (2i)] were prepared by reactions of the corresponding acetonitrile complexes [n = 1 (1a), 4 (1b)] with the appropriate isocyanide. Ab initio quantum-chemical methods at the RHF and single-point MP2 levels of theory were applied to the investigation of the structure, bonding, oxidation potential, and relative isomeric stability at the model complexes trans- and cis-[(PH3)2(CO)2(L)W(⋮C−CHCH2)] m + [L = Cl- (m = 0), NCMe (m = 1), CNMe (m = 1), or CO (m = 1)], which also comprise the related carbonyl and chloride species, allowing a comparison of the effects of the Cl-, NCMe, CNMe, and CO ligands, which are shown to follow their electron π-donor/acceptor properties. The electrochemical behavior of complexes 2a−i, as well as that of the related carbonyl, phosphine [L = CO; n = 1 (3a), 4 (3b); L = PMe3, n = 1 (4a)] and phosphinodithiocarboxylate [n = 1 (5a), 4 (5b)] compounds, was investigated by cyclic voltammetry and controlled potential electrolysis in aprotic media and at a Pt electrode. The oxidation potential follows the order of the net π-electron acceptor minus σ-donor character of the ligands, and from the observed linear dependence on the electrochemical P L ligand parameter it was possible to estimate the values of the electron-richness (E S) and polarizability (β) parameters for the binding metal fragments containing alkenyl-carbyne ligands, indicating they exhibit rather low electron-richness and polarizability, which are accounted for by the very strong π-electron acceptance of the coordinated alkenyl-carbyne groups. These ligands are activated toward proton loss by anodic oxidation of their complexes.

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