Acetate-catalyzed hydroboration of CO₂ for the selective formation of methanol-equivalent products

Abstract

The acetate anion is a highly robust and effective catalyst for the selective hydroboration of CO2 to methanol-equivalent products.

Organocatalytic insertion into C–B bonds by in situ generated carbene: mechanism, role of the catalyst, and origin of stereoselectivity

“…21) with the “g09default” keywords. As we all know, the DFT method which includes both exchange and correlation energies has become one of the most powerful tools for mechanistic studies on organocatalytic, 22 enzymatic 23 and organometallic 14,24 reactions. Compared with other popular density functionals for calculating organic thermochemistry, the B3LYP functional is still recognized as the most robust and versatile functional for predicting reliable geometries and vibrational frequencies, and it does not suffer from numerical noise of the relatively low integration grid and is faster than the meta-hybrid GGAs.…”

Ph2PCH2CH2B(C8H14) and Its Formaldehyde Adduct as Catalysts for the Reduction of CO2 with Hydroboranes

“…In 2013, Fontaine and co-workers reported the first example of a metal-free catalyst for the reduction of CO 2 to the methanol level using an ambiphilic phosphinoboronate catalyst ( I in Scheme ) and up to four different commercial hydroboranes: HBcat, pinacolborane (HBpin), 9-borabicyclo[3.3.1]­nonane (H-BBN), and BH 3 ·SMe 2 . Since then, a limited number of metal-free catalysts have been reported, mostly involving strong bases or ambiphilic species. , Among them, a few phosphinoborane systems turned out to be efficient, easily accessible catalysts for this reaction. As mentioned above, Fontaine and co-workers developed a series of phosphinoboronate catalysts, which turned out to be very active, ,, especially when using BH 3 as the reductant.…”

Mechanism of Hydroboration of CO2Using an Fe Catalyst: What Controls the Reactivity and Product Selectivity?

“…Besides the substrate-dependent nature, the product distribution is, to some extent, also dependent on the nature of the metal ions, the presence of external additives such as Lewis acids and bases, etc. Substrate-dependent reduction products suggest that the substrate controls the mechanism of CO 2 activation, and an in-depth understanding of intricate mechanistic steps and the nature of rate-determining steps is needed for further development. , Second, the reported reaction is based on a rare Fe catalyst, but the literature precedent reveals that the mechanism and reactivity vary dramatically if alternate metal ions such as Ni/Co/Mn are used. ,− Moreover, understanding the mechanism of CO 2 activation by first-row transition elements is challenging due to the involvement of different spin states, various spin configurations, and intricate mechanistic steps.…”