Research articles

Ortho-C–H and meta-C–H functionalization of arenes is well developed; however, para-C–H functionalization is more challenging. Now, a method for the synthesis of para-functionalized anilides from arylhydroxylamines and O- and S-nucleophiles is reported. The process uses fluorosulfuryl imidazolium triflates at low temperature and probably comprises O-fluorosulfonation, followed by N–O bond cleavage and nucleophilic addition.

Electrochemical routes to commodity chemicals are increasingly important to decarbonize the chemicals industry. Now, an electrochemical route to sulfonate products using CO₂ and SO₃²⁻ as building blocks has been reported, expanding the scope of electrochemical CO₂ reduction.

Alkyl alcohols are attractive surrogates for alkyl halides in the Suzuki–Miyaura cross-coupling reactions, but methods to activate the C–O bond are underdeveloped. Now a Ni-catalysed arylation is reported that uses aryl boronic esters and tertiary alcohols, through in situ alcohol silylation.

C14-functionalized steroids are pharmaceutically valuable, but their synthesis is challenging. Now a chemoenzymatic route is reported featuring a key biocatalytic C14α-hydroxylation, enabled by protein engineering of a C14α-hydroxylase (CYP14A) from Cochliobolus lunatus. Dehydration and olefin functionalization of the biocatalytic reaction products provides C14-functionalized steroids.

The synthesis of ammonia from dinitrogen is a vital reaction. Now, ligands prepared based on density functional theory calculations are used with a molybdenum trichloride complex for the production of up to 60,000 equiv. ammonia based on the catalyst, with a molybdenum turnover frequency of 800 equiv. min⁻¹.

The tailored synthesis of heterostructured intermetallic nanomaterials (iNMs) is challenging. Now, a galvanic replacement strategy is reported for the construction of a library of iNMs. Layered interfacial growth produces intermetallic heterostructures with controllable compositions, structures and interfaces.

The selective functionalization of strong, neutral C(sp³)–H bonds, such as in alkanes, is synthetically challenging. Now, a transition-metal- and photosensitizer-free strategy employing allyl bromides as reagents and sodium fluoride as an activator has been developed for the selective C(sp³)–H functionalization of alkanes, cycloalkanes and other relatively unreactive molecules.

Controlling the number and arrangement of ligands around metalloclusters is challenging. Now, a method for imparting site-differentiation to homoleptic clusters is reported in which the site-differentiation pattern is dictated by the steric profile of the incoming ligand.

Controlling the self-assembly of large coordination cages is challenging owing to entropic costs and difficulties in error correction. Now an array of large cages prepared by the rational design of alterations that allow for the tuning of the dihedral angle between pentagonal subunits is reported.

1,3-Disubstituted bicyclo[1.1.1]pentanes are linear bioisosteres for para-substituted benzene rings; however, the lack of practical reagents for the introduction of bicyclopentane currently impedes their application, especially in drug development. Now, stable thianthrenium-based bicyclopentane reagents are reported and their use in O-, N- and C-alkylation reactions demonstrated.

The heavy analogues of ynolates or ketenyl anions have not yet been studied. Here the synthesis, isolation and characterization of a sila-ketenyl anion, the silicon analogue of a ketenyl anion, are reported through the reaction of silyl-radical anions with CO.

A lack of guiding principles limits the preparation of two-dimensional (2D) materials prepared by a solution-phase growth route. Now, a general qualitative model for 2D material growth is proposed and applied to fabricate more than 30 nanomaterials, allowing 2D growth to be controlled by only tuning the reaction concentration or temperature.

Photoinduced catalytic systems typically consist of a transition metal catalyst and a photoredox catalyst. Now spiro-fluorene-indenoindenyl-Rh(I) complexes are reported as a single catalytic system that extends the scope of C–H borylation of arenes and [2+2+2] cycloaddition of alkynes to challenging substrates under irradiation with blue light.

Carbon- and silicon-based triplet diradicals with two unpaired electrons are proposed as intermediates in organic and organometallic reactions but their isolation is challenging. Now, isolable 1,3-disilapyrroles are reported to act as organosilicon-based delocalized triplet diradicals and mediate the cleavage of the CO triple bond and C(sp³)–H bond activation.

Hydrogen peroxide is an important industrial feedstock but its synthesis is energy intensive. Now, a highly efficient Ga-N₅ atomic site is reported with a high solar-to-chemical conversion efficiency for direct photocatalysis of water into hydrogen peroxide.

Controlled radical polymerization of fluorinated monomers typically synthesizes fluoropolymers of limited molecular weights with poor control. Now the controlled copolymerization of various fluoroalkenes under ambient conditions is reported by combining a redox-relay pathway and thermally activated delayed fluorescence catalysis.

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.

Complex molecule synthesis involves speculative retrosynthetic planning and resource-intensive experimental evaluation. Now, a complementary strategy is reported that combines human-generated synthetic plans with computational prediction to accelerate this process. A machine learning model was trained to predict the yield of radical cyclization and guide the syntheses of clovane sesquiterpenoids.

BODIPYs possessing boron-stereogenic centres are rare and it is challenging to develop catalytic methodologies to enantioselectively prepare these molecules. Now, a palladium-catalysed desymmetric intramolecular C–H arylation reaction for the enantioselective synthesis of boron-stereogenic BODIPYs is reported, which gives access to various six- to nine-membered chiral boron heterocycles with good enantioselectivity.

Preparing enantioenriched aliphatic amines from readily available feedstocks is challenging to achieve. Now, direct enantioconvergent amination of racemic secondary alcohols using a variety of aliphatic primary amines is reported, catalysed by chiral iridium and phosphoric acid species. This atom-economical strategy streamlines the enantioselective synthesis of N-containing commercial drugs and analogues.