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A new class of bis‐cyclometalated rhodium(III) catalysts containing two inert cyclometalated 6‐tert‐butyl‐2‐phenyl‐2H‐indazole ligands and two labile acetonitriles is introduced. Single enantiomers (>99 % ee) were obtained through a chiral‐auxiliary‐mediated approach using a monofluorinated salicyloxazoline. The new chiral‐at‐metal complex is capable of catalyzing the visible‐light‐induced enantioselective α‐cyanoalkylation of 2‐acyl imidazoles in which it serves a dual function as the chiral Lewis acid catalyst for the asymmetric radical chemistry and at the same time as the photoredox catalyst for the visible‐light‐induced redox chemistry (up to 80 % yield, 4:1 d.r., and 95 % ee, 12 examples)., A new chiral‐at‐metal rhodium(III) complex composed of two cyclometalated 2‐phenyl‐2H‐indazole ligands and two labile acetonitrile ligands permits the photoinduced enantioselective cyanoalkylation of 2‐acyl imidazoles. The new catalyst serves a dual function as a chiral Lewis acid catalyst for the asymmetric radical chemistry and at the same time as the photoredox catalyst for the visible‐light‐induced redox chemistry.

The mechanism of [2 + 2] cycloadditions activated by visible light and catalyzed by bis-cyclometalated Rh(iii) and Ir(iii) photocatalysts was investigated, combining density functional theory calculations and spectroscopic techniques. Experimental observations show that the Rh-based photocatalyst produces excellent yield and enantioselectivity whereas the Ir-photocatalyst yields racemates. Two different mechanistic features were found to compete with each other, namely the direct photoactivation of the catalyst–substrate complex and outer-sphere triplet energy transfer. Our integrated analysis suggests that the direct photocatalysis is the inner working of the Rh-catalyzed reaction, whereas the Ir catalyst serves as a triplet sensitizer that activates cycloaddition via an outer-sphere triplet excited state energy transfer mechanism., The mechanism of [2 + 2] cycloadditions activated by visible light and catalyzed by bis-cyclometalated Rh(iii) and Ir(iii) photocatalysts was investigated, combining density functional theory calculations and spectroscopic techniques.

The nickel-catalysed transposition of a carbon–carbon double bond of N-allyl and N-homoallyl amides is described. While the transposition of acyclic amides gave very high Z-selectivity of the enamides, corresponding cyclic N-allyl amides led exclusively to the E-configured products. Thereby, we realised a stereodivergent approach to enamides that is dependent on the structure of the amide substituents. When homoallylic substrates are used, a temperature-controlled single transposition to a Z-allylic amide derivative at low temperature or a double transposition to an E-enamide at elevated temperature could be achieved.