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Various computational methods were employed to investigate the zwitterion formation, a critical step for the reaction of monoethanolamine with CO 2 , in five solvents (water, monoethanolamine, propylamine, methanol and chloroform) to probe the effect of hydrogen bond capacity of solvents on the reaction of amine with CO 2 occurring in the amine-based CO 2 capture process. The results indicate that the zwitterion can be formed in all considered solvents except chloroform. For two pairs of solvents (methanol and monoethanolamine, propylamine and chloroform) with similar dielectric constant but different hydrogen bond capacity, the solvents with higher hydrogen bond capacity (monoethanolamine and propylamine) facilitate the zwitterion formation. More importantly, kinetics parameters such as activation free energy for the zwitterion formation are more relevant to the hydrogen bond capacity than to dielectric constant of the considered solvents, clarifying the hydrogen bond capacity could be more important than dielectric constant in determining the kinetics of monoethanolamine with CO 2 ., (Copyright © 2020. Published by Elsevier B.V.)

A highly novel method of direct synthesis of 2-aryl-3-sulfenylindoles in moderate to good yields was developed via one-pot tandem reaction of readily available α-aminocarbonyl compounds and catalytic amount of benzenamines with RSSR. Unlabelled Image • High total yield up to 94% • Simple condition • Stable raw material and broad [ABSTRACT FROM AUTHOR]

• High total yield up to 92%. • Short time required. • Stable raw material and broad. A novel and efficient method for the synthesis of 2- t -amino-2-imino-carbonyl (C) and 2-amino-2-oxocarbonyl (D) compounds has been discovered through a copper-promoted oxidating amidation reactions between α-amino -carbonyl compounds and amines. Promoted by the crucial copper species, perfect selectivity and good to excellent yields could be achieved. This transformation is achieved through C N bond oxidative cleavage and formation a novel C N bond. This reaction system has a broad reaction scope, providing a facile pathway for the α-functionalization of α-amino ketones. [ABSTRACT FROM AUTHOR]

Abstract: A highly efficient sp3–sp3 carbon–carbon bond formation system was developed for the aerobic ruthenium-catalyzed oxidative cross-dehydrogenative coupling reaction between tertiary amines and sp3 C–H compounds in the presence of RuCl3/O2, thus giving the corresponding α-functionalized amines. Compared with the reported method, H2O2 or t BuOOH was replaced successfully by economical and facile oxygen as the oxidant. Three types of activated C–H bonds for pronucleophiles were evaluated in this system. All these features combined are in accordance with important prospective green chemistry aspects. [Copyright &y& Elsevier]

Abstract: A mild, selective, and efficient protocol for the synthesis of γ-aminoalkyl butenolides via the oxidative coupling between tertiary amines and siloxyfurans catalyzed by simple copper salts was developed. Compared with the reported method, our method employs copper catalyst instead of the expensive rhodium catalyst. Besides TBHP, both O2 and H2O2 can also be utilized as oxidant to effect the coupling. [Copyright &y& Elsevier]