Basic heteroarenes are a ubiquitous feature of pharmaceuticals and bioactive molecules, and Minisci-type additions of radical nucleophiles are a leading method for their elaboration. Despite many Minisci-type protocols that result in the formation of stereocenters, exerting control over the absolute stereochemistry at these centers remains an unmet challenge. We report a process for addition of prochiral radicals, generated from amino acid derivatives, to pyridines and quinolines. Our method offers excellent control of both enantioselectivity and regioselectivity. An enantiopure chiral Brønsted acid catalyst serves both to activate the substrate and induce asymmetry, while an iridium photocatalyst mediates the required electron transfer processes. We anticipate that this method will expedite access to enantioenriched small-molecule building blocks bearing versatile basic heterocycles.

This perspective examines the progress that has been made in using non-covalent interactions to control regioselectivity and site-selectivity in catalysis.

The use of noncovalent interactions to direct transition-metal catalysis is a potentially powerful yet relatively underexplored strategy, with most investigations thus far focusing on using hydrogen bonds as the controlling element. We have developed an ion pair-directed approach to controlling regioselectivity in the iridium-catalyzed borylation of two classes of aromatic quaternary ammonium salts, leading to versatile meta-borylated products. By examining a range of substituted substrates, this provides complex, functionalized aromatic scaffolds amenable to rapid diversification and more broadly demonstrates the viability of ion-pairing for control of regiochemistry in transition-metal catalysis.

Artificial metalloenzymes (ArMs) result from the incorporation of an abiotic metal cofactor within a protein scaffold. From the earliest techniques of transition metals adsorbed on silk fibers, the field of ArMs has expanded dramatically over the past 60 years to encompass a range of reaction classes and inspired approaches: Assembly of the ArMs has taken multiple forms with both covalent and supramolecular anchoring strategies, while the scaffolds have been intuitively selected and evolved, repurposed, or designed in silico . Herein, we discuss some of the most prominent recent examples of ArMs to highlight the challenges and opportunities presented by the field.

Selective functionalization at the meta position of arenes remains a significant challenge. In this work, we demonstrate that a single anionic bipyridine ligand bearing a remote sulfonate group enables selective iridium‐catalyzed borylation of a range of common amine‐containing aromatic molecules at the arene meta position. We propose that this selectivity is the result of a key hydrogen bonding interaction between the substrate and catalyst. The scope of this meta‐selective borylation is demonstrated on amides derived from benzylamines, phenethylamines and phenylpropylamines; amine‐containing building blocks of great utility in many applications.