We have studied base-promoted homolytic aromatic substitution (BHAS) of 1-(2-iodobenzyl)-pyrrole mediated by W(CNAr)6 (CNAr = arylisocyanide) photoreductants in aromatic solvents. Upon one-photon 445-nm excitation (5 mol % substrate loading) of W(CNDipp)6 (CNDipp = 2,6-diisopropylphenylisocyanide), nearly complete conversion is afforded after one hour of irradiation in 1,2-difluorobenzene. Addition of 0.2 M tetrabutylammonium hexafluorophosphate (TBAPF6) results in slightly diminished conversions; and the reaction proceeds catalytically in the presence of electrolyte, with an order of magnitude increase in TON. Of interest is that formation of seven-coordinate [WI2(CNDipp)5] does not terminate BHAS catalysis in 1,2-difluorobenzene.

Photoredox catalysis mediated by tungsten(0) arylisocyanides in 1,2-difluorobenzene

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.