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The conversion of the ubiquitous greenhouse gas CO2 to valuable organic products is much sought after. Herein, the hydrogenation of CO2 to C1 products with an 80% yield in water is reported using a novel catalyst, porous-silica-supported Au nanoparticles (Au/SiO2). In the presence of a Lewis acid, boric acid, the Au/SiO2 catalyst enables an efficient conversion of amine-captured CO2 to methanol, formate, and formamide. A mechanistic study involving isotopic labelling suggests that methanol production in the catalytic process arises from the direct hydrogenation of formate. Most importantly, this one-pot, two-step process is able to convert CO2 in air at ambient pressures to C1 products in the absence of an organic solvent. Furthermore, the catalyst is readily recycled without further purification or reactivation and shows no significant decrease in catalytic activity after four reaction cycles in a reusability test. [ABSTRACT FROM AUTHOR]

A series of bifunctional phase-transfer catalysts with a quaternary onium center and a hydrogen-bonding donor group were prepared for the fixation of CO2 with commercially available epoxides under mild conditions by using a CO2 balloon (1 atm). In the presence of 2.5 mol% of achiral bifunctional phase-transfer catalysts, cyclic carbonates were obtained in good to excellent yields (up to 95%). Additionally, optical carbonates and epoxides were obtained through the kinetic resolution of rac-epoxides by 1 mol% of chiral bifunctional phase-transfer catalysts with low enantioselectivities. These catalysts featured a simple synthetic route, good modularity and high efficiency. [ABSTRACT FROM AUTHOR]

Commercially available NaOH powder is shown to be an efficient transition-metal-free initiator for the catalytic hydroboration of aldehydes, ketones, alkynes and alkenes with HBpin and 9-BBN under mild conditions. Combined experimental and theoretical studies suggest that the catalytically active species is a boron hydride generated in situ from the reaction mixture. [ABSTRACT FROM AUTHOR]