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The N‐methylation reaction of amines with methanol via the borrowing‐hydrogen strategy is an important method for the construction of C−N bonds. Compared with other C1 sources, such as toxic formaldehyde or expensive formic acid, methanol is more suitable for N‐methylation reactions due to its eco‐friendliness and low price. Using this strategy, various types N‐methylated products, including biological and pharmaceutical molecules have been prepared. Here, we present a thorough survey of decades of articles showing current developments in N‐methylation reactions with methanol. We discuss homogenous, heterogenous and light‐driven catalytic systems for both N‐methylation and N,N‐dimethylation reactions. This review presents the shortcomings of current developments and provides future development progress in N‐methylation reactions with methanol. [ABSTRACT FROM AUTHOR]

The support is pivotal for stabilizing single metal atoms and contributes to enhance the catalytic activity of single-atom catalysts. With the merits of versatile structures, tailored electronic structure, as well as high stability, manganese oxide octahedral molecular sieve (OMS-2) can be used as an ideal support to immobilize single atoms. Herein, we report a single-atom Pd catalyst (Pd1–OMS-2) that can afford a silane conversion of above 99% with silanol selectivity of over 99% using water as oxidant under mild conditions, outperforming the original OMS-2. The as-synthesized catalyst exhibits great functional group tolerance and good catalyst stability without aggregation after reaction. And the enhanced catalytic activity is attributed to the decoration of atomic Pd and the increase in content of oxygen vacancies. Characterization of Pd1–OMS-2 indicates that the highly dispersed Pd species is trapped into the framework of OMS-2 by substituting Mn ions, which results in the formation of Pd–O bonds with the adjacent O atoms. [ABSTRACT FROM AUTHOR]

Diethyl carbonate (DEC) was synthesized from ethanol and ethyl carbamate (EC) over Mg–Y composite oxides with excellent yield. Mg–Y composite oxide calcined at 450 °C demonstrated excellent catalytic activity and 70.3% yield was obtained. Note that the production capacity of catalysts (PCC) reached 5987 mgDEC gcat−1 h−1 under the optimized conditions, which was far higher than that reported in previous literature reports. Furthermore, other carbamates such as methyl carbamate (MC) and butyl carbamate (BC) could be also successfully converted into the corresponding dialkyl carbonates. The catalyst could be easily recovered four times under identical conditions. The origin of the catalytic performance was studied using various characterization techniques, and the TPD results showed that the MgY-450 catalyst exhibited more accessible moderate and strong basic sites, which was beneficial to expressing excellent catalytic performance. [ABSTRACT FROM AUTHOR]

With the continuous increase in CO2 emissions, primarily from the combustion of coal and oil, the ecosystem faces a significant threat. Therefore, as an effective method to minimize the issue, the Reverse Water Gas Shift (RWGS) reaction which converts CO2 towards CO attracts much attention, is an environmentally‐friendly method to mitigate climate change and lessen dependence on fossil fuels. Nevertheless, the inherent thermodynamic stability and kinetic inertness of CO2 is a big challenge under mild conditions. In addition, it remains another fundamental challenge in RWGS reaction owing to CO selectivity issue caused by CO2 further hydrogenation towards CH4. Up till now, a series of catalysis systems have been developed for CO2 reduction reaction to produce CO. Herein, the research progress of the well‐performed heterogeneous catalysts for the RWGS reaction were summarized, including the catalyst design, catalytic performance and reaction mechanism. This review will provide insights into efficient utilization of CO2 and promote the development of RWGS reaction. [ABSTRACT FROM AUTHOR]

Heterogeneously catalyzed N‐formylation of amines to formamide with CO2/H2 is highly attractive for the valorization of CO2. However, the relationship of the catalytic performance with the catalyst structure is still elusive. Herein, mixed valence catalysts containing Cu2O/Cu interface sites were constructed for this transformation. Both aliphatic primary and secondary amines with diverse structures were efficiently converted into the desired formamides with good to excellent yields. Combined ex and in situ catalyst characterization revealed that the presence of Cu2O/Cu interface sites was vital for the excellent catalytic activity. Density functional theory (DFT) calculations demonstrated that better catalytic activity of Cu2O/Cu(111) than Cu(111) is attributed to the assistance of oxygen at the Cu2O/Cu interface (Ointer) in formation of Ointer‐H moieties, which not only reduce the apparent barrier of HCOOH formation but also benefit the desorption of the desired N‐formylated amine, leading to high activity and selectivity. [ABSTRACT FROM AUTHOR]

Heterogeneously catalyzed N‐formylation of amines to formamide with CO2/H2 is highly attractive for the valorization of CO2. However, the relationship of the catalytic performance with the catalyst structure is still elusive. Herein, mixed valence catalysts containing Cu2O/Cu interface sites were constructed for this transformation. Both aliphatic primary and secondary amines with diverse structures were efficiently converted into the desired formamides with good to excellent yields. Combined ex and in situ catalyst characterization revealed that the presence of Cu2O/Cu interface sites was vital for the excellent catalytic activity. Density functional theory (DFT) calculations demonstrated that better catalytic activity of Cu2O/Cu(111) than Cu(111) is attributed to the assistance of oxygen at the Cu2O/Cu interface (Ointer) in formation of Ointer‐H moieties, which not only reduce the apparent barrier of HCOOH formation but also benefit the desorption of the desired N‐formylated amine, leading to high activity and selectivity. [ABSTRACT FROM AUTHOR]

Synthesis of cyclic carbonates by the cycloaddition of CO2 in flue gas offers a promising path to valorize CO2. Here we demonstrate that the PP1,4Br/ZnCl2 catalytic system can efficiently capture CO2 from flue gas and in situ catalyze the cycloaddition reaction to form cyclic carbonates. Under optimized conditions, up to 98% yield of cyclic carbonates is achieved. This catalytic system displays good tolerance to substrates with oxygen- and silicon-based functional groups, and exhibits excellent recyclability and water resistance for potential applications. In addition, the results of scale-up experiments (750 mmol) show that the PP1,4Br/ZnCl2 system has outstanding CO2 capture and conversion ability. The residual content of CO2 in the system after the reaction was 600 ppm, which realizes the integration of CO2 capture and transformation into value-added chemicals. [ABSTRACT FROM AUTHOR]