ABSTRACT
The first single-crystal X-ray structures of substituted vanadyl phthalocyanine materials reveal the high-valence vanadium ions (denoted as V(IV)), whose coordination by a highly electron-deficient ligand is facilitated by an axial oxo group. The metal center of the hydrophilic VâO core, encapsulated in F-rich hydrophobic pockets, reaches a coordination number of 6 by binding an additional H(2)O that, in turn, hydrogen-bonds with ketones, resulting in solvent-induced variable solid-state architectures. Fluoroalkyl (R(f)) ligand substituents hinder π-π stacking interactions and favor ordered long-range packing, as well as the facile formation of film materials that exhibit high thermal stability and oxidation resistance. Reversible redox chemistry and spectroscopic studies in both solution and the solid-state indicate single-site isolation in both phases and an R(f)-induced propensity for electron uptake and inhibition of electron loss. Repeated redox cycles reorganize the thin films to accommodate Li(+) ions and facilitate their migration. The facile reduction, combined with high stability and ease of sublimation imparted by the R(f) scaffold that suppresses oxidations, recommends the new materials for sensors, color displays, electronic materials, and redox catalysts, as well as other applications.
ABSTRACT
Zinc perfluoro-fluoroalkyl-phthalocyanine, synthesized in high yield, does not exhibit electron loss, does not aggregate in solution, is photostable and produces (1)O(2) in very high quantum yields. Aerobic photo-oxygenation of an external substrate occurs without catalyst self-oxidation. The encapsulation of a metal center in a refractory organic environment could guide the design of other viable catalysts for oxygenation of substrates either for synthesis or for oxidative destruction of organic or biological molecules, under reaction conditions that include the use of only air and light.
