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Modulation of random heteropolymers results in globular polymer clusters with catalytic activity mimicking proteins.

Novel concepts in asymmetric catalysis have the potential to open up previously inaccessible reaction space. This Review reflects on the origins of an area that has undergone dramatic recent advancement: the use of chiral anions in asymmetric catalysis. Details of a selection of the latest examples are also given.

Our increasing understanding of non-covalent interactions involving aromatic systems is reviewed, and the use of these insights in the design of small-molecule catalysts and enzymes is surveyed.

Supramolecular hosts can readily self-assemble from simple components and allow remarkable chemical rate enhancements and product selectivity utilising defined microenvironments and specific host–guest interactions. This Review Article describes recent conceptual and catalytic advances made in this field.

Transition metal catalysts containing gold present exciting new opportunities for chemical synthesis. Experimental and computational data is reviewed to present our current understanding of homogeneous gold catalysis, focusing on previously unexplored reactivity and its application to the development of new methodology.

Although methods exist to construct secondary stereocentres containing both a C–F and C–H bond, the ability to form a tertiary C–F bond, remote from pre-existing activating groups, remains challenging. Now, C–F tertiary, benzylic stereocentres have been constructed through a Pd-catalysed enantioselective Heck reaction of acyclic alkenyl fluorides with arylboronic acids.

The integration of biological and chemocatalytic routes can be used to convert acetone–butanol–ethanol fermentation products efficiently into ketones by palladium-catalysed alkylation, leading to a renewable method for the alternative production of petrol, jet and diesel blend stocks in high yield.

Covalent inhibitors are powerful entities in drug discovery. Now the amino acid selectivity and reactivity of a diverse electrophile library have been assessed proteome-wide using an unbiased workflow. This comparative analysis and the probes described could help guide the discovery and design of covalent ligands targeting residues beyond cysteine.

An analysis of key intermediates relevant to gold(I) catalysis has been performed using density functional theory. A bonding model is proposed whereby the reactivity of gold(I)-coordinated carbenes is dependent on carbene substituents and ancillary ligands that dictate where these gold structures lie on a continuum ranging from a metal-stabilized singlet carbene to a metal-coordinated carbocation.

Combinations of enzymatic and chemo-catalysis can result in powerful synthetic transformations. Here, encapsulation of Au(I) or Ru(II) within a supramolecular assembly prevents diffusion of the organometallic complexes into solution where they can compromise the activity of an enzyme. This strategy has been applied to tandem reactions employing supramolecular host–guest complexes and enzymes in the catalysis of organic transformations.

The chemical conversion of N-heterocyclic carbene molecules attached to catalytic particles is monitored at high spatial resolution using synchrotron-radiation-based infrared nanospectroscopy.

The facile synthesis of a stable Au(III) cationic complex is described; this gold catalyst exhibits hard, oxophilic Lewis acidity, enabling selective conjugate additions and a [2 + 2] cycloaddition reaction.

Here it is shown that chiral dithiophosphoric acids can catalyse the intramolecular hydroamination and hydroarylation of dienes and allenes to generate heterocyclic products in exceptional yield and enantiomeric excess. A mechanistic hypothesis is presented that involves the addition of the acid catalyst to the diene, followed by S_N2′ displacement of the resulting dithiophosphate intermediate, and mass spectroscopic and deuterium labelling studies support the proposed mechanism.

Insights on the mechanistic differences between artificial metalloenzymes (ArMs) with non-native metal centres and the free cofactor or natural enzymes are scarce. Now, a detailed mechanistic analysis of a cyclopropanation reaction catalysed by such an ArM is provided, revealing intriguing differences to the natural system.

With palladium catalysts, chemists can manipulate ordinarily inert carbon–hydrogen bonds to build useful molecules from simple building blocks. How the catalysts guide this process has just become a bit clearer.

Global profiling of hyper-reactive tryptophan sites across whole proteomes using tryptophan chemical ligation by cyclization (Trp-CLiC) reveals a systematic map of tryptophan residues that participate in cation–π interactions, including functional sites that can regulate protein-mediated phase-separation processes.

Mechanistic studies of reductive elimination that forms aryl–aryl bonds from simple mono- and dinuclear gold phosphine complexes are disclosed. The observed rates for reductive elimination are unusually fast, even at temperatures as low as –52 °C, providing insight into the fundamental reactivity of oxidized organogold complexes.

Homogeneous, heterogeneous and enzyme catalysts each provide distinct advantages and disadvantages. This Perspective discusses important approaches, benefits and challenges of constructing hybrid catalysts, revealing their potential to improve various catalytic processes.

Supported single-atom catalysts often feature a distinct reactivity when compared to traditional heterogeneous or homogeneous systems. Here the authors introduce a supported iridium single-atom catalyst for carbenoid O–H insertion characterized by a remarkable selectivity for aliphatic versus aromatic alcohols, unlike its homogeneous counterpart.

N-heterocyclic carbenes (NHCs) have been widely used for the formation of monolayers but self-assembly methods come with drawbacks such as need for dry environment or using specifically-synthesized precursors. Here, the authors demonstrate an approach for surface-anchoring of NHCs which overcomes these limitations by using electrochemically-assisted deprotonation.

Heterogeneous catalysts are generally more readily recycled than homogeneous catalysts, but the latter are more easily modified to tune reactivity and selectivity. Here, the dendrimer coating of gold nanoparticle catalysts is shown to be a surrogate for the ligands of homogeneous catalysts. Tuning of product distribution and reaction selectivity is possible when these catalysts are employed in a fixed-bed flow reactor.

Combining the benefits of homogeneous and heterogeneous processes may lead to important advances in catalysis. This has now been achieved using selectively oxidized and supported electrophilic platinum nanoparticles that catalyse a range of π-bond activation reactions previously only catalysed homogeneously.

The hydration and ion pairing of metal-organic supramolecular cages plays a crucial role in their interaction with guests but is difficult to quantify with standard analysis. Here, the authors show that microwave microfluidics to measure the hydration and ion pairing of two tetrahedral metal-organic cages.

There is a growing demand for renewable transportation fuels. This protocol describesthe production of an acetone-butanol-ethanol mixture in Clostridiumacetobutylicum as well as its reaction to form long-chain ketones for testing as car or jet fuel.