Solar-powered surface functionalization of multiwall carbon nanotubes for sp3 C-H bond arylation and coenzyme regeneration

One of the most important yet challenging applications of solar energy is its role in the synthesis of solar-derived fine chemicals and the regeneration of coenzymes through an in-situ surface-functionalized photocatalytic system. In this approach, we have developed an in-situ surface functionalized donor-acceptor photocatalytic system (MWCNT-TBA), where a multiwall carbon nanotube (MWCNT) is directly bonded to a TBA moiety (2,4,6-tribromoaniline) serving as a light harvester. This function exhibits dual functionalities with high selectivity in direct sp3 C-H bond arylation with excellent yields (99.16 %). It facilitates photo redox arylation of heteroarenes via sp3 C-H bonds using aryl diazonium salts and also achieves efficient photo-regeneration of coenzymes (1,4-NADH) up to 46.25 %. This general and straightforward approach provides an alternative for arylheteroaryl linkages to transition metals and highly selective photo-regeneration of coenzymes.