Articles in 2023

Chiral α-quaternary amino and glycolic acids have found use in medicinal applications. Although their synthesis through α-alkylation is well known, synthesis via α-arylation remains challenging. Now, palladium-catalysed methods for the enantioselective α-arylation of amino acid- and glycolic acid-derived heterocycles, azlactones and 5H-oxazol-4-ones, using aryl bromides, are reported.

The use of gaseous sulfuryl fluoride in sulfur(VI) fluoride exchange reactions is a challenge. Now, a flow set-up for the on-demand generation and onward reaction of sulfuryl fluoride, from sulfuryl chloride, is reported. The process produces fluorosulfate and sulfamoyl fluoride analogues of small molecules, peptides and proteins.

Water electrolysis can produce clean hydrogen, but it is limited by the slow anodic oxygen evolution reaction. Now, a local electronic manipulation strategy for stabilizing high-valence Ru single site catalysts has been developed. The catalyst demonstrates efficient bifunctional activity for water electrolysis.

Controlling the reaction pathway in electrochemical CO₂ reduction for the selective production of hydrocarbons or oxygenates is challenging. Now, control over atomic immiscibility in Cu and Cu–Ag alloyed catalysts can steer CO₂ reduction products from ethylene towards ethanol.

Cation–anion exchange between dimers to prepare mixed aggregates with Mg–Ae (alkaline earth) bonding (Ae = Mg, Ca, Sr, Ba) is reported. Considerable electron transfer from the (BDI)Mgˉ anion (BDI, β-diketiminate) to Ae and Na atoms is observed, and the reactivity of these electron-rich complexes with Na–Mg–Ae bonding is discussed.

Nimbolide is an inhibitor of poly(ADP)-ribosylation-dependent ubiquitin E3 ligase RNF114. A modular synthesis of nimbolide and its analogues is now reported, using a sulfonyl hydrazone-mediated etherification and a radical cyclization strategy. These analogues give insight into structure–activity relationships and some have superior poly(ADP-ribose) polymerase-1 trapping activity relative to nimbolide.

The unexpected phenomenon of rapid, long-distance transport of an ultrathin and uniform metal film on two-dimensional crystals is reported at temperatures well below the melting points of all of the materials involved. The effect is generalizable and may offer possibilities in confined space chemistry, as well as in two-dimensional crystal growth and devices.

A nanodroplet sequential fusion strategy is presented that can be used to precisely synthesize branched silica nanotrees, creating complex and functional inorganic superstructures.

By removing water from crystalline molecular complexes, microporous metal–organic framework glasses are formed. The glasses can be obtained in monolithic shapes by melt-quenching.

Triaryloxonium salts are used as aryne precursors under mild and operationally simple conditions, allowing high functional-group tolerance, and cycloaddition reactions are used to trap the arynes generated.

A flow microreactor-enabled method is reported for the stereo- and regioselective synthesis of multisubstituted alkenes by reductive syn-boryllithiation and syn-borylsodiation of arylacetylenes. Reaction of the alkyne substrate with a naphthalenide reductant and a boron electrophile generates a syn-β-borylalkenyl alkali metal intermediate, which can react with a range of electrophiles.

Sustained Mars exploration requires in situ synthesis of vital chemicals such as oxygen. Now a data-driven platform for synthesizing oxygen-producing electrocatalysts from Martian meteorites using robotics and artificial intelligence is developed, allowing automated screening of the optimal catalyst formula. This approach demonstrates materials discovery under challenging circumstances and without human intervention.

The chemical synthesis of jasmonates is typically low yielding and can be laborious, whereas their extraction can be costly or environmentally hazardous. Now a de novo biosynthesis of jasmonic acid and its derivatives, methyl jasmonate and jasmonoyl isoleucine, is reported, using an engineered baker’s yeast.

Enantioselective synthesis of medium-sized rings by organocatalytic cycloadditions offers opportunities that are complementary to metal-catalysed cycloadditions. This Review discusses the ability of organocatalytic cycloadditions to synthesize stereodefined medium-sized ring architectures, critically evaluates current synthetic strategies, and highlights avenues for further development.

Mathematical functions can be found throughout nature and have importance for studying the assembly of single particles into branched superstructures. Here, Wedderburn–Etherington number patterns are produced in branched mesoporous silica nanotrees.

Strained cyclic allenes are short-lived intermediates that confine a functional group with a preferred linear geometry, an allene, into a small ring, inducing strain-driven reactivity. Now, 2,3-azacyclic and 2,3-oxacyclic allenes are generated and trapped using cycloaddition reactions, generating complex heterocycles that bear a large fraction of sp³-hybridized atoms.

Enantioselective γ-lactonization of unactivated C(sp³)–H bonds is a challenge using chemical methods. Now the biocatalytic enantioselective synthesis of γ-lactones from aliphatic carboxylic acids is reported, using a reengineered fatty acid hydroxylase, P450_BSβ. Crystallographic and computational analyses show the observed γ-regioselectivity arises from the mutants introduced into P450_BSβ.

A β-lactone compound — globilactone A — has been discovered through genome mining and heterologous expression of a biosynthetic gene cluster. Biosynthetic investigations unveiled the mechanism of the formation of the cyclopentane-β-lactone core.