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Different electrolytes applied in the aqueous electrocatalytic CO 2 reduction reaction (CO 2 RR) considerably influence the catalyst performance. Their concentration, species, buffer capacity, and pH value influence the local reaction conditions and impact the product distribution of the electrocatalyst. Relevant properties of prospective solvents include their basicity, CO 2 solubility, conductivity, and toxicity, which affect the CO 2 RR and the applicability of the solvents. The complexity of an electrochemical system impedes the direct correlation between a single parameter and cell performance indicators such as the Faradaic efficiency; thus the effects of different electrolytes are often not fully comprehended. For an industrial application, a deeper understanding of the effects described in this review can help with the prediction of performance, as well as the development of scalable electrolyzers. In this review, the application of supporting electrolytes and different solvents in the CO 2 RR reported in the literature are summarized and discussed.

Although catalytic reductions, cross‐couplings, metathesis, and oxidation of CC double bonds are well established, the corresponding catalytic hydroxylations of CH bonds in alkanes, arenes, or benzylic (allylic) positions, particularly with O2, the cheapest, “greenest”, and most abundant oxidant, are severely lacking. Certainly, some promising examples in homogenous and heterogenous catalysis exist, as well as enzymes that can perform catalytic aerobic oxidations on various substrates, but these have never achieved an industrial‐scale, owing to a low space‐time‐yield and poor stability. This review illustrates recent advances in aerobic oxidation catalysis by discussing selected examples, and aims to stimulate further exciting work in this area. Theoretical work on catalyst precursors, resting states, and elementary steps, as well as model reactions complemented by spectroscopic studies provide detailed insight into the molecular mechanisms of oxidation catalyses and pave the way for preparative applications. However, O2 also poses a safety hazard, especially when used for large scale reactions, therefore sophisticated methodologies have been developed to minimize these risks and to allow convenient transfer onto industrial scale.

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A modular approach for the synthesis of highly ordered porous and chiral auxiliary (Evans auxiliary) decorated metal-organic frameworks is developed. Our synthesis strategy, which uses known porous structures as model materials for incorporation of chirality via linker modification, can provide access to a wide range of porous materials suitable for enantioselective separation and catalysis. Chiral analogues of UMCM-1 have been synthesized and investigated for the enantioseparation of chiral compounds in the liquid phase and first promising results are reported.

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Direct epoxidation of propene with hydrogen peroxide vapor was conducted in a microstructured reactor containing TS-1 catalyst coatings. At 140 °C, 1 bar, 5 vol % hydrogen peroxide, and 15 vol % propene, productivities of more than 1 kg of propene oxide per kg of catalyst and hour are obtained in lab scale, which is in an industrially highly relevant range. Excellent selectivities to propene oxide based on propene of >90% were reached. Potential and need for improvement lie in the propylene oxide selectivity based on hydrogen peroxide, which was observed to be about 25%. By increasing the molar excess of propene to about 6.6, propylene oxide selectivities related to hydrogen peroxide of up to 60% have been observed in the pilot plant.