ZrO 2 -supported Pt clusters;i i) the amidation of triglycerides under gaseous NH 3 catalyzed by high-silica H-beta (Hb)z eolite at 180 8C; iii)the Hb-promoted synthesis of nitrilesf rom triglycerides and gaseous NH 3 at 220 8C. These methods are widely applicable to the transformation of various triglycerides (C 4 -C 18 skeletons)i nto the corresponding amines,a mides, and nitriles.

Catalytic methylation of aromatic hydrocarbons using CO2 and H2 as a methylating agent was conducted over a combination of TiO2-supported Re (Re(1)/TiO2; Re = 1 wt %) and H-β (SiO2/Al2O3 = 40) in a batch reactor. Catalytic methylation of m-xylene was performed, and this catalyst combination demonstrated excellent performance for the synthesis of methylbenzenes, giving a high yield of total methylated products (10 and 57%, as calculated on the basis of CO2 and m-xylene, respectively), while generating relatively small amounts of byproducts such as demethylated and dearomatized products as well as CO and CH4 in the gas phase under the investigated reaction conditions (p CO2 = 1 MPa, p H2 = 5 MPa, T = 240 °C, t = 20 h). Our catalysts were also found to perform well for the methylation of toluene, providing a high yield and high selectivity for methylated products compared with the other investigated catalyst combinations. In addition to conducting conventional-type catalyst research, we used a data science approach based on machine learning techniques to identify important input variables that govern the catalytic performance, enabling optimization of the catalyst for the methylation reaction. Compared with the catalysts optimized using the conventional approach, the improved Re/TiO2 catalyst with a Re loading amount of 1.8 wt %, which was optimized with the aid of ML, exhibited greater activity toward the methylation of benzene using CO2/H2.

A one-pot, acceptorless dehydrogenative method, using a carbon-supported Pt catalyst (Pt/C) along with KOtBu, has been developed for the synthesis of 2,4,6-trisubstituted pyrimidines from secondary and primary alcohols, and amidines. The reaction takes place efficiently using a wide range of substrate scopes (32 examples with isolated yields up to 92%). The Pt/C catalyst that promotes this process is reusable and has a higher turnover number (TON) than those employed in previously reported methods. The results of mechanistic studies suggest that the process takes place through a pathway that begins with Pt-catalyzed acceptorless dehydrogenation of the alcohol substrate, which is followed by sequential condensation, cyclization, and dehydrogenation. Measurements of the turnover frequency combined with the results of density functional theory calculations on different metal surfaces suggest that the adsorption energy of H on the Pt surface is optimal for the acceptorless dehydrogenation process, which causes the higher catalytic activity of Pt over those of other metals.

The direct catalytic esterification of amides that leads to the construction of C−O bonds through the cleavage of amide C−N bonds is a highly attractive strategy in organic synthesis. While aliphatic and aromatic alcohols can be readily used for the alcoholysis of activated and unactivated amides, the introduction of phenols is more challenging due to their lower nucleophilicity in the phenolysis of unactivated amides. Herein, we demonstrate that phenols can be used for the phenolysis of unactivated amides into the corresponding phenolic esters using a simple heterogenous catalytic system based on CeO2 under additive‐free reaction conditions. The method tolerates a broad variety of functional groups (>50 examples) in the substrates. Results of kinetic studies afforded mechanistic insights into the principles governing this reaction, suggesting that the cooperative effects of the acid–base functions of catalysts would be of paramount importance for the efficient progression of the C−N bond breaking process, and consequently, CeO2 showed the best catalytic performance among the catalysts explored.

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A combined catalyst comprising TiO 2 -supported Re (Re(1)/TiO 2 ; Re = 1 wt%) and H-MOR (SiO 2 /Al 2 O 3 = 90) was found to promote the methylation of benzene using CO 2 and H 2 . This catalytic system exhibited high performance with regard to the synthesis of methylated benzenes and gave high yields of total methylated products (up to 52 % benzene-based yield and 42 % CO 2based yield) under the reaction conditions employed in this study (p CO2 = 1 MPa; p H2 = 5 MPa; T = 250°C; t = 20 h) in a batch reactor. Catalyst screening demonstrated that a combination of Re(1)/TiO 2 and H-MOR (SiO 2 /Al 2 O 3 = 90) exhibited superior performance compared to other combinations of supported metal catalysts and zeolites in terms of both yield and selectivity for methylated benzenes.

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