Photophysics and Photochemistry of Conformationally Restricted Triarylmethanes: Application as Photoredox Catalysts

Abstract

The three aryl rings of triarylmethanes are free to rotate. However this free rotation can be restricted on either by bridging the aryl rings through covalent bonds or through hetero- atoms resulting in the formation of Conformationally Restricted Triarylmethanes (CRT). The photophysics and photochemistry of these CRTs, like 9-arylxanthenes (oxygen bridging), 9-arylthioxanthenes (sulfur bridging), 9, 10-dihydro-9-arylacridines (nitrogen bridging), 9-arylfluorenes (bridging through carbon–carbon covalent bond) have recently been the subject of number studies. Various applications of CRT molecules have been devel- oped out of which application as photoredox catalyst is undoubtedly the most important. In this chapter, we have highlighted recent development of various CRT molecules, their photophysics, photochemistry and an application in the field of photoredox catalysis.