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Asymmetric catalytic photoelectrochemical reactions for the construction of complex compounds are underdeveloped. Now, merging photoelectrochemistry with asymmetric catalysis has enabled the dehydrogenative [2 + 2] photocycloaddition between alkyl ketones and alkenes affording enantioenriched cyclobutanes.

Octahedral chiral-at-metal complexes have chirality based on the metal centre, but reactivity occurs at the organic ligands. Here, the authors report such a complex as a highly active Brønsted base catalyst, with loadings down to 0.02 mol% for asymmetric Michael additions and 0.25 mol% for aza-Henry reactions.

The use of electrochemistry in asymmetric catalysis can prove challenging, not least due to the difficulty of achieving chemo- and stereoselectivity in combination with very reactive electrochemically generated intermediates. Here, catalytic asymmetric electrosynthesis is reported for the synthesis of 1,4-dicarbonyl compounds with high enantiomeric excess, including compounds with all-carbon quaternary stereocentres. The chiral-at-metal catalyst activates the substrate towards anodic oxidation in addition to controlling the enantioselectivity of the process.

Despite intensive research on photoexcited molecules, stereocontrol of direct bond formation upon photoexcitation remains limited. Here the authors expand the research on stereocontrolled bond forming photochemistry and introduce the catalytic asymmetric synthesis of chiral nitrogen heterocycles.

For asymmetric catalysis, chiral cobalt catalysts have garnered considerable attention, but there remains an absence of reactive chiral cobalt catalysts constructed exclusively from achiral ligands. Herein, the authors report a reactive chiral-at-cobalt catalyst comprised entirely of achiral ligands, and its application in visible-light-activated enantioselective transformation of isoxazoles into chiral 2H-azirines.

The amination of C–H bonds is a sustainable approach to prepare important nitrogen-containing molecules; however, regio- and stereoselectivity is difficult to control. Now the synthesis of α-monosubstituted and α,α-disubstituted α-amino acids from abundant carboxylic acids has been achieved through Fe-catalysed asymmetric intermolecular C(sp³)–H amination by directed stereocontrolled nitrene insertion.

A straightforward method for synthesizing optically active α-amino acids from abundant carboxylic acids has been developed. Based on a nitrene-mediated stereocontrolled 1,3-nitrogen shift, this approach provides access to a large variety of unnatural α-amino acids with aryl, allyl, propargyl and alkyl side chains and enables late-stage amination of carboxylic-acid-containing drugs.

A chiral iridium complex serves as a sensitizer for photoredox catalysis and at the same time provides very effective asymmetric induction for the enantioselective alkylation of 2-acyl imidazoles; the metal centre simultaneously serves as the exclusive source of chirality, the catalytically active Lewis acid centre, and the photoredox centre.

Self-assembly processes usually yield symmetric compounds. Here, the authors report the distortion of a symmetric hydrogen-bonded resorcin[4]arene cage upon encapsulation of an iridium complex.

Optically active compounds can be prepared using chiral catalysts. This protocol describes rhodium- and iridium-based asymmetric catalysts that rely exclusively on metal-centered chirality. Applications to asymmetric photoredox catalysis are provided.