Metal-Catalyzed Hydride Transfer from Alcohols to Photoexcited Dipyridophenazine.

Dipyridophenazine (dppz) is known to react with alcohols upon photoexcitation into an n-π* transition at 378 nm to yield dihydrodipyridophenazine (dppzH ). This process occurs via H-atom abstraction from alcohols and subsequent disproportionation of the dppzH radical species, to the final product. This reaction shows a primary kinetic isotope effect (KIE = 4.

Photodriven Multi-electron Storage in Disubstituted Ru(II) Dppz Analogues.

Four derivatives of the laminate acceptor ligand dipyrido-[3,2-a:2',3'-c]phenazine (dppz) and their corresponding ruthenium complexes, [Ru(phen)2 (dppzX2 )](2+) , were prepared and characterized by NMR spectroscopy, ESI-MS, and elemental analysis. The new ligands, generically denoted dppzX2 , were symmetrically disubstituted on the distal benzene ring to give 10,13-dibromodppz (dppz-p-Br), 11,12-dibromodppz (dppz-o-Br), 10,13-dicyanodppz (dppz-p-CN), 11,12-dicyanodppz (dppz-o-CN). Solvated ground state MO calculations of the ruthenium complexes reveal that these electron-withdrawing substituents not only lower the LUMO of the dppz ligand (dppz(CN)2 View Article and Find Full Text PDF

Enantiomeric separations of ruthenium (II) polypyridyl complexes using HPLC with cyclofructan chiral stationary phases.

The enantiomeric separation of 21 ruthenium (II) polypyridyl complexes was achieved with a novel class of cyclofructan-based chiral stationary phases (CSPs) in the polar organic mode. Aromatic derivatives on the chiral selectors proved to be essential for enantioselectivity. The R-napthylethyl carbamate functionalized cyclofructan 6 (LARIHC CF6-RN) column proved to be the most effective overall, while the dimethylphenyl carbamate cyclofructan 7 (LARIHC CF7-DMP) showed complementary selectivity.