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The development of a mild and general method for C(sp3)−H functionalization of cyclic amines has been an ongoing challenge. In this work, we describe the copper‐catalyzed enantioselective C(sp3)−H alkynylation of unactivated cyclic 2‐iodo‐benzamide under photo‐irradiation by intramolecular 1,5‐hydrogen atom transfer (HAT). The employment of a new bisoxazoline diphenylamine ligand, in conjunction with 1,1′‐bi‐2‐naphthol, which significantly improved the reduction potential of the copper complex, was the key to success of this chemistry. Mechanistic and computational studies supported that the new copper complex served the dual role as a photoredox and coupling catalyst, the reaction went through a radical process, and the intramolecular 1,5‐HAT process was involved in the rate‐limiting step. Apart from the broad substrate scope including unprecedented benzocyclic amines, this method also showed excellent diastereoselectivity in 2‐monosubstituted cyclic amines via substrate control. [ABSTRACT FROM AUTHOR]

A visible-light-driven radical-mediated strategy for the in situ generation of aza- ortho-quinone methides from 2-vinyl-substituted anilines and alkyl radical precursors is described. This process enables an efficient multicomponent reaction of 2-vinylanilines, halides, and sulfur ylides, and has a wide substrate scope and good functional group tolerance. Treatment of the cycloaddition products with a base leads to densely functionalized indoles in a single-flask operation. [ABSTRACT FROM AUTHOR]

An abstract of the article "Visible-Light Induced Oxidant-Free Oxidative Cross-Coupling for Constructing Allylic Sulfones from O lefins and Sulfinic Acids" by authors including Lingling Zhang, Hong Yi, and Yi Luo.

The first examples of a visible-light-mediated decarboxylation/oxidative amidation of α-keto acid with aliphatic and aromatic primary amines are described. [ABSTRACT FROM AUTHOR]