[Fe(bpy)Cl ₃ X][bpy H] complexes: synthesis, characterization and theoretical studies towards visible-light photocatalytic hydroxyethylation of quinoline

AbstractA series of [Fe(bpy)Cl3X][bpy·H] (X = Cl, Br, I) complexes were prepared from direct treatment of FeCl3·6H2O with 2,2′-bipyridine in the presence of an HX solution. The complexes were characterized by IR, UV–Vis, XRDP, and cyclic voltammetry techniques. Electrochemical studies revealed a possible reduction to form the corresponding Fe0 complexes. A single crystal of [Fe(bpy)Cl4][bpy·H] displayed important H–Cl/Cl–H, H–H, H–C/C–H, and H–N/N–H interactions which were corroborated by a Hirshfeld surface analysis as well as MEP, QTAIM, and NCI studies, and complemented by HOMO/LUMO calculations at the B3LYP/cc-pVDZ + LANL2DZ level. In addition, the complexes displayed catalytic activity for the visible-light-driven the formation of 1-quinolin-4-yl-ethanol from quinoline under acidic conditions.Keywords: Iron complexbipyridinehydroxyethylation Disclosure statementNo potential conflict of interest was reported by the authors.AcknowledgmentsThe authors thank N. Zavala, A. Nuñez, L. Triana, and M.C. Martínez for the technical support.Additional informationFundingFunded by CONACYT (Project No. A1-S-18230 and fellowship for Z.G.R.M., CVU: 860116).