title: How the Coordinated Structures of Ag(I) Catalysts Affect the Outcomes of Carbon Dioxide Incorporation into Propargylic Amine: A DFT Study.
abstract: Density functional theory calculations have been carried out to explore the detailed mechanisms for carbon dioxide incorporation of N-unsubstituted propargylic amine catalyzed by Ag(I) catalysts. We show that the reaction undergoes substrate adsorption or displacement, isomerization from amine-coordinated species to the alkyne-coordinated species, CO2attack, and proton transfer, giving the carbamate intermediate. Subsequently, the reaction would bifurcate at the intermolecular ring-closing step, which produces five-membered ring (5MR) and six-membered ring (6MR) products at the same time, thus raising a regioselectivity issue. Our calculations reveal that the outcomes of the reaction critically depend on the coordination number and the basicity of the ligands. Higher coordinate number and stronger basicity of the ligands would stabilize the 5MR transition state over the 6MR counterpart. Such a preference can be rationalized by using transition state energy decomposition. All of these results could promote the rational design of noble metal/organic base combined catalysts with higher selectivity.
authors.affiliation: College of Chemistry and Chemical Engineering, Department of Chemistry, Xiamen University , Xiamen 361005, People's Republic of China.
authors.forename: Ruming
authors.identifier: 0000-0002-2639-6520
authors.initials: R
authors.lastname: Yuan
authors.affiliation: College of Chemistry and Chemical Engineering, Department of Chemistry, Xiamen University , Xiamen 361005, People's Republic of China.
authors.forename: Baohuan
authors.initials: B
authors.lastname: Wei
authors.affiliation: College of Chemistry and Chemical Engineering, Department of Chemistry, Xiamen University , Xiamen 361005, People's Republic of China.
authors.forename: Gang
authors.initials: G
authors.lastname: Fu