Reviews & Analysis

This Review describes the general trends and implications of heterogeneities within individual catalyst particles as observed by modern spatiotemporal spectroscopy. It discusses how catalytic materials have been found to display heterogeneities in structure, composition and reactivity in space and time. The implications of these findings for future catalyst design are also described.

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.

Thiolate-protected gold surfaces and interfaces are archetypal systems in various fields of current research in nanoscience, materials science, inorganic chemistry and surface science. Examples include self-assembled monolayers of organic molecules on gold, passivated gold nanoclusters and molecule–gold junctions. This Review discusses recent experimental and theoretical breakthroughs that highlight common features of gold-sulfur bonding in these systems.

Redox sites can be incorporated within dendrimers — highly branched, well-defined macromolecules — at specific locations, such as their core, branching points, periphery or inner cavities. These dendrimers can serve to functionalize surfaces, and electron-transfer processes at their redox sites show promise for various applications ranging from metallo-protein modelling to sensing to catalysis.

Photosynthesis starts when light is absorbed and the associated excitation energy is directed to reaction centres by antenna complexes. The principles learned from studying these complexes are described in this Review, and provide the framework from which the authors suggest how to elucidate strategies for designing light-harvesting systems that route the flow of energy in sophisticated ways.

Peptide macrocycles have a number of important applications. Among other things, the reduced conformational freedom of the cyclic structure enables strong binding to the extended contact regions of protein–protein complexes. Here, emerging methods directed towards the synthesis of these valuable molecules are reviewed.

Crystalline networks containing empty cavities can host a variety of molecules but also promote reactions between guests. Through robust crystallinity and a pseudo-solution state (dynamic movements) within their pores, these crystalline molecular flasks enable the direct observation of species — including unstable intermediates — during a reaction by in situ X-ray diffraction.

The programmable and reliable hybridization of DNA strands has enabled the preparation of a wide variety of structures. This Review discusses how, in addition to these static assemblies, the process of displacing — and ultimately replacing — strands also makes possible the construction of dynamic systems such as logic gates or autonomous walkers.

Chemically derived graphene oxide (GO) has recently moved on from simply being a graphene precursor to attracting interest for its own properties. This Review discusses how the presence of oxygenated groups and domains of sp²- and sp³-hybridized carbons makes GO tunable and promising for various physical and biological applications.

Most synthetic polymers are made from petroleum and their production is currently not sustainable. RAFT polymerization has emerged as a powerful technique to control the synthesis of such polymers, thus expanding further their applications. This Review discusses the sustainability of RAFT in terms of process and materials.

Aerosol particles are crucially important to the chemistry of the atmosphere, influencing both climate and air quality. This Review discusses progress in understanding the radical-initiated heterogeneous oxidation of atmospheric aerosols, focusing on the reaction mechanisms and kinetics, and also their effects on the physico-chemical properties of particles.

The synthesis or separation of chiral compounds is crucial for many areas of chemistry, with chiral solids having important roles as catalysts or separating agents. This Review covers recent progress and future avenues for developing methods of preparing chiral solids from achiral starting materials.

Rare-earth metal dialkyl complexes can be readily transformed into the corresponding cationic monoalkyl species — which have been shown to catalyse a range of (co)polymerization processes — as well as into polyhydride complexes that have unique structures and a rich reaction chemistry.

The field of organocatalysis has grown rapidly in the past decade to become, along with metal catalysis and biocatalysis, a third pillar of asymmetric catalysis. Here, progress in the use of organocatalytic cascade reactions for total synthesis is reviewed. The elegance and efficiency of such cascades mean that they have emerged as a powerful tool in synthetic organic chemistry.

The formation of single-layer-thick molecular networks at metal surfaces is governed by the interplay between intermolecular and interfacial interactions. This Review highlights how, with films built by vacuum deposition, these interactions can be modulated to form substrates that may be useful as catalysts or templates for further deposition steps.

Nature's enzymes are remarkably efficient at catalysing highly specific reactions with extraordinary selectivity. The ability to design enzymes for any desired reaction is a huge challenge. Here, the advances in the development of artificial enzymes are discussed with a particular focus on the computational advances that bring this challenge closer to reality.

Encapsulating guest molecules inside host structures ranging from soft, flexible enzymes to rigid, porous zeolites has led to developments in many areas, including catalysis, sensing and separation. This Review highlights how metal–organic frameworks — materials formed by linking metal centres with organic ligands — can combine softness with regularity to produce dynamic, yet crystalline, structures that may prove useful for a range of applications.

The development of general synthetic strategies for the prepartion of oligonucleotides and peptides has enabled them to be made routinely — often using automated systems. Making complex oligosaccharides is much less straightforward, but advances in areas such as one-pot multi-step protecting-group manipulations, stereoselective glycosylation protocols and chemo-enzymatic methods are offering new opportunities for carbohydrate chemistry.

Ring-opening metathesis polymerization (ROMP) is a powerful and highly functional-group-tolerant technique for synthesizing polymers. However, this tolerance presents a great challenge for the selective introduction of functional end-groups. This Review discusses currently available end-functionalization strategies and also highlights factors to be considered when choosing the most appropriate approach.

Transition metals can form extremely short bonds with very high bond orders. Bimetallic chromium complexes are the best-known examples, and quintuple bonds have been reported. This Review covers recent developments in the synthesis and theoretical description of quintuply bonded transition metal coordination compounds.