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  • The properties of polymers depend on monomer composition and chain length, but regulating these structural features during polymer synthesis is a challenge. Now Hecht and co-workers report a photoswitchable catalyst system that can repeatedly be switched between ON and OFF states, allowing remote control of the polymerization process. Furthermore, copolymerization with control over monomer incorporation is demonstrated.

    • Fabian Eisenreich
    • Michael Kathan
    • Stefan Hecht
  • Predicting metal–support combinations that can afford stable single-atom catalysts remains a complex problem. Now, a computational method is reported that can be used to screen interaction strengths between metals and supports and identify those pairs that generate strongly adsorbed single-atom catalysts.

    • Nolan J. O’Connor
    • A. S. M. Jonayat
    • Thomas P. Senftle
  • Organic synthesis relies on the ability to convert simple starting materials into compounds with greater molecular complexity. Here, Trost and co-workers use branched aldehydes as nucleophiles for asymmetric Mannich reactions, and the products of these reactions as electrophiles for the addition of a range of carbon nucleophiles. This provides a simple, stereodivergent route to 1,3-aminoalcohols.

    • Barry M. Trost
    • Chao-I (Joey) Hung
    • Elumalai Gnanamani
  • Electrolysis uses clean electricity to form chemical products but typical water electrolysis produces hydrogen which is hard to store oxygen which is a waste gas. Here, paired electrolysis is performed with an palladium membrane reactor to carry out two organic reactions simultaneously. The dense palladium membrane enables the two reactions to proceed in different solvents and the reaction rates and selectivities can be independently controlled.

    • Rebecca S. Sherbo
    • Roxanna S. Delima
    • Curtis P. Berlinguette
  • Cross-coupling of aryl compounds is one of the most powerful carbon–carbon bond forming reactions available, and typically involves the use of expensive and scarce palladium salts. Here Bedford and co-workers show that iron can be an effective catalyst for Suzuki biaryl couplings.

    • Harry M. O’Brien
    • Mattia Manzotti
    • Robin B. Bedford
  • The conversion of carbon dioxide into multi-carbon alcohols would enable the synthesis of sustainable liquid fuels with high energy densities. Now, vacancy-engineered core–shell copper-based catalysts are able to shift the selectivity of electrochemical CO2 reduction into alcohols instead of alkenes, as obtained with bare-copper catalysts.

    • Tao-Tao Zhuang
    • Zhi-Qin Liang
    • Edward H. Sargent
  • The proper verification of the stability of metal oxide catalysts for water electrolysis in acid electrolyte remains unresolved. Here, the ‘stability number’ is introduced to evaluate the dissolution mechanisms of various iridium-based oxides and to facilitate benchmarking of catalysts independent of loading, surface area or involved active sites.

    • Simon Geiger
    • Olga Kasian
    • Serhiy Cherevko
  • The Fe protein of nitrogenase contains a redox-active [Fe4S4] cluster that plays a key role in electron transfer and substrate reduction. Here, Hu and co-workers show that the Fe protein of Methanosarcina acetivorans can reduce CO2 and CO to hydrocarbons under ambient conditions.

    • Martin T. Stiebritz
    • Caleb J. Hiller
    • Yilin Hu
  • Dynamic kinetic resolution (DKR) allows the conversion of both enantiomers of a racemic mixture into a single enantiomer of product, and requires both a stereoselective reaction and a means of rapidly racemizing the starting materials. Here, a highly stereoselective iridium-catalysed DKR of secondary allylic alcohols is reported, with mechanistic studies implying that substrate racemization is achieved through carbon–oxygen bond cleavage.

    • Jianguo Liu
    • Suppachai Krajangsri
    • Pher G. Andersson
  • The generation of hydrogen fuel from water and visible light requires photoelectrodes that are inexpensive, stable and highly active. Now, Luo, Grätzel and co-workers report Cu2O photocathodes that reach these goals. Incorporation into an unassisted solar water splitting device gives ~3% solar-to-hydrogen conversion efficiency.

    • Linfeng Pan
    • Jin Hyun Kim
    • Michael Grätzel
  • The structural modification of inactive materials to effectively engineer active catalysts is very attractive. Here, layered crystalline Pd3P2S8 is transformed by electrochemical lithiation into amorphous Li-incorporated nanodots. This process turns the inert parent material into a highly active and stable hydrogen-evolving catalyst.

    • Xiao Zhang
    • Zhimin Luo
    • Hua Zhang
  • Catalytic oxybromination is an important strategy for the upgrade of methane. Here, Pérez-Ramírez and co-workers employ operando photoelectron photoion coincidence spectroscopy as well as kinetic analyses and molecular simulations to unravel the complex reaction mechanism.

    • Vladimir Paunović
    • Patrick Hemberger
    • Javier Pérez-Ramírez
  • Methane borylation allows for the functionalization of an otherwise unreactive compound, enabling its use as a one-carbon building block; however, competing diborylation presents a selectivity issue. Now, a metal–organic-framework-based catalyst highly selective for monoborylation is reported. The selectivity is due to the reaction taking place within the catalyst pores, which excludes the formation of the larger diborlyated product.

    • Xuan Zhang
    • Zhiyuan Huang
    • Omar K. Farha
  • Reactive metal–support interactions can tune the activity of heterogeneous catalysts, but have mainly been reported for oxide supports. Now, the metal–support interaction of platinum with MXenes at moderate temperature is reported, using the water-gas shift reaction as an example to showcase the properties of a representative catalyst.

    • Zhe Li
    • Yanran Cui
    • Yue Wu
  • Access to renewable hydrogen represents an important target for the success of the hydrogen economy. Now, a one-pot method is presented for the conversion of cellulosic biomass into hydrogen via formic acid as the intermediate, followed by its application to a fuel cell.

    • Ping Zhang
    • Yan-Jun Guo
    • Yang Li
  • Energy-based descriptors have proven very successful in recent years despite their impracticality from an experimental viewpoint. Here, a universal descriptor based only on electronegativities and coordination numbers is put forward to predict the activity of carbon-based single-metal-atom catalysts for three of the most important electrocatalytic reactions. This descriptor can be extended to metal–macrocycle complexes with similar coordination environments.

    • Haoxiang Xu
    • Daojian Cheng
    • Xiao Cheng Zeng