Research articles

The reactivity of transient carbocations provides interesting synthetic opportunities, but the selectivity control is challenging. Now, catalytic access to carbocation intermediates via metal-nitrenoid transfer into alkenes is reported and their regiocontrolled elimination is achieved, allowing the production of allylic lactams.

The carboazidation of olefins represents an effective strategy to introduce both carbon and nitrogen substituents into hydrocarbons, but asymmetric versions of this reaction remain elusive. Now, an iron-catalysed asymmetric radical carboazidation is introduced that yields chiral halogenated organoazides in high enantiomeric ratios.

Tetraarylmethanes display special properties due to their spherical nature and are applied in various areas, but strategies for their asymmetric production are lacking. Now, their enantioselective synthesis is reported and in vitro studies indicate their potential as anticancer agents.

Obtaining spatially resolved spectroscopic information for catalysts under working conditions remains challenging. Here, an approach that combines X-ray absorption spectroscopy with microtomography is introduced and showcased for the selective catalytic reduction of NO_x with ammonia over a Cu-SSZ-13 washcoated monolith catalyst.

The rational design of efficient water oxidation electrocatalysts is paramount to the development of electrochemical devices. Now, a Co-TiO₂ single-site catalyst is presented for alkaline water oxidation with high intrinsic activity, and its mechanism has been studied by grand canonical quantum mechanics calculations and in situ techniques.

Fe–N–C materials are a promising alternative to platinum for catalysing the oxygen reduction reaction in acidic polymer fuel cells. Now, a ⁵⁷Fe Mössbauer study reveals that while these catalysts initially comprise two distinct FeN_x sites, a high-spin FeN₄C₁₂ and a low- or intermediate-spin FeN₄C₁₀, only the latter is durable in operating conditions.

Electrochemical conversion of CO₂ into value-added chemicals holds promise to enable the transition to carbon neutrality, but enhancing the selectivity toward a specific hydrocarbon product remains a challenging task. Now, the authors present a Cu–polyamine hybrid catalyst that achieves Faradaic efficiency of 87% for ethylene and full-cell energy efficiency of 50%.

Preparative methods for thioester and tertiary amide formation are currently missing in the biocatalysis repertoire. Now, a mutation of serine to cysteine in the catalytic triad of an acyltransferase expands its synthetic capability to generate these compounds while retaining its natural activity towards alcohols.

Platinum-group-metal-free, non-iron catalysts are highly desirable for the oxygen reduction reaction at proton exchange membrane (PEM) fuel cell cathodes, as they avoid the detrimental Fenton reactions. Now, a cobalt and nitrogen co-doped carbon catalyst with atomically dispersed porphyrin-like CoN₄C₁₂ sites is reported with an improved activity and durability in PEM fuel cell conditions.

Although the light-promoted Sabatier reaction has great potential for CO₂ remediation strategies, its mechanism is not fully understood. Now, a steady-state isotopic kinetic analysis coupled with infrared spectroscopy reveals important aspects of this hydrogenation process over a NiO_x/La₂O₃@TiO₂ composite catalyst.

Despite their promising optical properties, organolead halide perovskites are not frequently used in photocatalysis due to their low stability in water. Here, a long-lasting semiconductive organolead iodide layered crystalline material with the ability to perform overall water splitting is introduced.

Controlling the regioselectivity in the coupling of simple aromatics is challenging. Now, para–para selectivity is achieved during the aerobic dehydrogenative homocoupling of arenes through a shape-selective catalyst based on molecular palladium confined within the framework of zeolite materials.

Extensive research efforts in systems chemistry are directed to the development of in vitro systems that mimic complex natural networks. Now, stimuli-responsive nucleic acid-based networks conjugated to biocatalysts for the triggered and orthogonal control over biocatalytic cascades are reported.

Domino asymmetric electrophilic halocyclization is useful for the synthesis of polycyclic pharmaceutical compounds, but remains limited to the generation of fused rings. Now, the scope is extended to complex spirocycle products by a catalytic protocol involving an electron-rich thiourea catalyst.

The spatial segregation of distinct catalytic functionalities within the same material holds great promise for cascade or antagonistic reactions, but it remains challenging. Here, the authors report the successful realization of this approach for an efficient hierarchical porous silica catalyst featuring spatially separated sulfated zirconia and magnesium oxide.

The electrochemical nitrogen reduction reaction has recently attracted significant interest, but the true source of ammonia formation remains sometimes unclear. This Analysis reports a systematic investigation of the presence of nitrogen-containing species in a number of commercial catalysts, revealing substantial levels of NO_x⁻ and nitrides impurities for some of them.

Difunctionalization of alkenes can afford useful building blocks from readily available starting materials, but these reactions often show limitations in olefin scope. This work presents a catalyst-controlled enantioselective 1,1-arylboration of unactivated alkenes that is independent of directing groups.

Multimetal oxyhydroxides are among the most active catalysts for alkaline water oxidation, but tuning their properties remains a challenge. Now, the performance of NiFe- and FeCo-based catalysts is optimized with the incorporation of high-valence modulator metals, which shifts the active metals towards lower valence states and enables lower overpotentials.

Despite the efforts to tune their properties, the efficiency of tantalum nitride photoanodes falls short of the theoretical value. Here, a gradient Mg doping strategy is introduced to engineer tantalum nitride’s band structure and control its defects, leading to an applied bias photon-to-current efficiency of 3.25%.

The valorisation of plastic waste is highly desirable from an environmental perspective but generally yields low-value products. Now a method is disclosed to deconstruct plastic feedstocks into high-value hydrogen and carbon materials by means of an iron-based catalyst under microwave irradiation.