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A metal‐free convergent paired electrolysis strategy to synthesize benzylic amines through direct arylation of tertiary amines and benzonitrile derivatives at room temperature has been developed. This TEMPO‐mediated electrocatalytic reaction makes full use of both anodic oxidation and cathodic reduction without metals or stoichiometric oxidants, thus showing great potential and advantages for practical synthesis. This convergent paired electrolysis method provides a straightforward and powerful means to activate C−H bonds and realize cross‐coupling with cathodically generated species.

By merging electricity with sulfate, the Ritter-type amination of C(sp3)-H bonds is developed in an undivided cell under room temperature. This method features broad substrate generality (71 examples, up to 93% yields), high functional-group compatibility, facile scalability, excellent site-selectivity and mild conditions. Common alkanes and electron-deficient alkylbenzenes are viable substrates. It also provides a straightforward protocol for incorporating C-deuterated acetylamino group into C(sp3)-H sites. Application in the synthesis or modification of pharmaceuticals or their derivatives and gram-scale synthesis demonstrate the practicability of this method. Mechanistic experiments show that sulfate radical anion, formed by electrolysis of sulfate, served as hydrogen atom transfer agent to provide alkyl radical intermediate. This method paves a convenient and flexible pathway for realizing various synthetically useful transformations of C(sp3)-H bonds mediated by sulfate radical anion generated via electrochemistry.

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A novel dinuclear oxygen-bridged chromium(II) complex of [(Ph 3 SiO)Cr 3 (THF)] 2 (μ-OSiPh 3 ) 2 (1) was successfully synthesized and structurally characterized. The crystal structure of complex 1 shows that the chromium centers adopt a tetrahedrally distorted square-planar coordination geometry. Complex 1 was tested for ethylene polymerization upon activation with and without aluminum alkyl cocatalysts. No ethylene polymerization activity was observed in the absence of aluminum alkyl cocatalysts; however, in the presence of methylaluminoxane (MAO), complex 1 demonstrates an unexpected transformation from ethylene polymerization to ethylene oligomerization, with the molar ratio of Al to Cr increasing from 50 to 1000. The activation of complex 1 with MAO was investigated by ESR and 29 Si NMR spectroscopy. It was found that the Ph 3 SiOÀ groups could be transferred from the chromium centers of complex 1 to the aluminum of MAO.

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