Germanium(iii) corrole complex: Reactivity and mechanistic studies of visible-light promoted N-H bond activations

Abstract

The [(TPFC)Ge(TEMPO)] (1, TPFC = tris(pentafluorophenyl)corrole, TEMPO = (2,2,6,6-tetramethylpiperidin-1-yl)oxyl) complex was characterized by X-ray diffraction and spectroscopic studies. EPR studies indicate that the weak Ge-O bond in 1 is photo-cleaved to form a tetra-coordinated germanium(iii) radical, [(TPFC)Ge(iii)]. DFT calculations show that the spin density on the germanium center in [(TPFC)Ge(iii)] has a significant s character. Under visible-light irradiation, 1 reacts rapidly with ammonia, primary/secondary aliphatic amines and aniline to produce (TPFC)Ge-NR¹R² (R¹R ² = HH, HⁿPr, HⁱPr, H^tBu, HPh, Et<inf>2</inf>, ⁱPr<inf>2</inf>) complexes in high yields (65-95%). © The Royal Society of Chemistry 2014.