Methylthiophenoxyl radical plays an important role as the active form of galactose oxidase (GO), which catalyzes oxidation of a primary alcohol to the corresponding aldehyde. Although many metal(II)‐phenoxyl radical species have been reported, only a few studies have been reported on the properties of methylthiophenoxyl radical‐metal complexes. We have prepared the group 10 metal (Ni, Pd and Pt) complexes of a salen‐type ligand with a methylthio group at para‐position of the two phenolate moieties and characterized them by X‐ray crystal structure analyses and various spectroscopic methods in order to understand the role of the methylthio moiety in phenoxyl radical metal complexes. The corresponding p‐methoxy substituted derivatives have been also characterized for comparison. All the one‐electron oxidized group 10 metal methylthiophenolate complexes have a relatively localized radical site on one of the two phenolate moieties in comparison to the one‐electron oxidized complexes of p‐methoxy derivatives and exhibit different properties dependent on the central metal ions.

To gain insights into the role of the proximal indole ring in the redox-active metal center as seen in galactose oxidase, we prepared the Cu(II)-salen-type complexes having a pendent indol-3-ylmethyl (1), methyl (2) or benzyl (3) group substituted on the ethylenediamine moiety and investigated the structures and redox properties by various physicochemical methods and theoretical calculations. Neutral complexes 1, 2, and 3 showed no significant difference in the UV-Vis-NIR and EPR spectra. One-electron oxidation of 1, 2, and 3 by addition of 1 equiv. of thianthrenyl radical gave [1]SbCl , [2]SbCl , and [3]SbCl , respectively, which could be assigned to relatively localized phenoxyl radical species. The cyclic and differential pulse voltammograms of [1]SbCl showed two redox waves with a large separation between the first and second redox potentials compared with the separations observed for [2]SbCl and [3]SbCl . This suggests that [1]SbCl is more stabilized than [2]SbCl and [3]SbCl . The NIR band of [1]SbCl showed a larger blue shift than that of [2]SbCl and [3]SbCl . The EPR spectrum of [2]SbCl exhibited an intense signal at the g value of 2 due to partial disproportionation to form the EPR active two-electron oxidized complex [2] , while the EPR intensity of [1]SbCl was much weaker than that of [2]SbCl . These results indicate that the pendent indole moiety stabilizes the Cu(II)-phenoxyl radical in [1]SbCl most probably by stacking with the phenoxyl moiety, which is further supported by DFT calculations.

The reaction mechanism of the cationic rhodium(i)–BINAP complex catalysed isomerisation of allylic amines was explored using the artificial force induced reaction method with the global reaction route mapping strategy.

A catalytic enantioselective proton migration of skipped enynes to allenes is developed. A newly identified chiral ferrocenyl phosphine ligand plays critical roles in controlling both regio-and enantioselectivity. The method offers a new concept to convert readily available and abundant feedstock hydrocarbons into high-value-added molecules by reconstituting C-H bond connectivity without relying on polar functional groups.

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