CO2 and anthropogenic waste materials as feedstock reagents in photocatalytic reactions

The field of photocatalysis in organic synthesis has seen a significant increase in research interest in recent years due to the appealing benefits that are associated with this branch of synthetic chemistry; photocatalysis enables unique transformations to be achieved via the light induced chemical processes which are typically inaccessible by conventional thermal approaches, while maintaining high reaction selectivity under mild conditions.1-4

The novel reactivities afforded by the use of photocatalysts in synthetic organic chemistry has the further benefit of allowing small, gaseous molecules to be used as reagents in reactions. Gaseous molecules such as carbon dioxide,5-7 sulfur dioxide,8-10 methane and other small hydrocarbons11, 12 have all featured in recent publications as feedstock reagents. This is a hugely exciting research area; by using photocatalysis it is feasible to convert these abundant, and thereby potentially inexpensive, small waste molecules into building blocks for valuable synthetic target products, thereby providing an economic incentive for investing in these technologies and approaches.

This field has potential for extensive further research: including the development of new photocatalysts, the discovery of novel synthetic reactions, and the testing of new experimental setups to improve the versatility of photocatalytic transformations in synthetic chemistry. Furthermore, this work will contribute to the goal of making organic chemistry more 'green': by using anthropogenic waste gases as feedstock reagents to synthesise valuable target molecules, and by developing new reactions that minimise our reliance on rare transition metals.