Ni–Fe alloy catalysts prepared by a simple hydrothermal method and subsequent H2 treatment were shown to be highly selective for the hydrogenation of various unsaturated carbonyls.

New sustainable approaches should be developed to overcome equilibrium limitation of dialkyl carbonate synthesis from CO2 and alcohols. Using tetraethyl orthosilicate (TEOS) and CO2 with Zr catalysts, we report the first example of sustainable catalytic synthesis of diethyl carbonate (DEC). The disiloxane byproduct can be reverted to TEOS. Under the same conditions, DEC can be synthesized using a wide range of alkoxysilane substrates by investigating the effects of the number of ethoxy substituent in alkoxysilane substrates, alkyl chain, and unsaturated moiety on the fundamental property of this reaction. Mechanistic insights obtained by kinetic studies, labeling experiments, and spectroscopic investigations reveal that DEC is generated via nucleophilic ethoxylation of a CO2‐inserted Zr catalyst and catalyst regeneration by TEOS. The unprecedented transformation offers a new approach toward a cleaner route for DEC synthesis using recyclable alkoxysilane.

Cu–Fe catalysts prepared from Cu–Fe layered double hydroxides (LDHs) exhibited high activity for dehydrogenation of alcohols under oxidant- and base-free conditions.

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A simple and practical method for direct synthesis of tetramethoxysilane (TMOS) from silica (SiO2) and methanol was achieved using a base catalyst and acetal as a dehydrant under carbon dioxide (CO2). The production of TMOS was strongly influenced by the kind of the acetal used, with 2,2-dimethoxypropane identified as the most effective dehydrant. We observed that the acetal used enabled the production of a high yield of dimethyl carbonate (DMC), which promoted the TMOS production. DMC is an intermediate product from the reaction of CO2 and methanol, which supported the SiO2 depolymerization process. When the reaction is conducted with 2,2-dimethoxypropane at 260 °C for 24 h, TMOS can be produced in up to 59% yield. For practical applications, the TMOS synthesis has been developed on a 250 mL and 1 L-scale reaction with constant yield (>50%) from various silica resources.