Can carbene be used for a metal free reduction of carbon dioxide?

Abstract

Reduction of \(\hbox {CO}_2\) to \(\hbox {CO}_2\)\(^-\) is a bottleneck in the conversion of \(\hbox {CO}_2\) into various value-added chemicals. Here, based on quantum chemical calculations, we propose that the complexation of \(\hbox {CO}_2\) with a carbene drastically reduces the electron affinity of \(\hbox {CO}_2\) and thus makes the reduction of \(\hbox {CO}_2\) spontaneous. Using various carbenes of different nucleophilicity, we have shown that the facile reduction of \(\hbox {CO}_2\) in the presence of a carbene can be achieved for a variety of carbenes, and hence, offers an attractive route for converting \(\hbox {CO}_2\) into various useful chemicals.

the reduction of CO\(_2\) to CO\(_2\) \(^-\) is a bottleneck in the conversion of CO\(_2\) into various value-added chemicals. There are two main challenges in converting CO\(_2\) to CO\(_2\) \(^-\). First, the high energy barrier associated with CO\(_2\) to CO\(_2^-\) reduction, and a low solubility of CO\(_2\) in water. We have shown that by using a carbene-CO\(_2\) complex rather a bare CO\(_2\), both of these limitations can be circumvented.