High Triplet Energy Iridium(III) Isocyanoborato Complex for Photochemical Upconversion, Photoredox and Energy Transfer Catalysis.

Cyclometalated Ir(III) complexes are often chosen as catalysts for challenging photoredox and triplet-triplet-energy-transfer (TTET) catalyzed reactions, and they are of interest for upconversion into the ultraviolet spectral range. However, the triplet energies of commonly employed Ir(III) photosensitizers are typically limited to values around 2.5-2.

Sensitized Photocatalytic CO Reduction With Earth Abundant 3d Metal Complexes Possessing Dipicolyl-Triazacyclononane Derivatives.

Complexes based on nitrogen and sulfur containing ligands involving 3d metal centers are known for the electrocatalytic reduction of CO However, photocatalytical activation has rarely been investigated. We herein present results on the light-driven CO reduction using either Ir(dFppy) [, dFppy = 2-(4,6-difluorophenyl)pyridine] or [Cu(xant)(bcp)], (, xant = xantphos, bcp = bathocuproine) as photosensitizer in combination with TEA (triethylamine) as sacrificial electron donor. The 3d metal catalysts have either dptacn (dipicolyl-triazacyclononane, ) or dpdatcn (dipicolyl-diazathiocyclononane, ) as ligand framework and Fe, Co or Ni as central metal ion.