Tetra­kis(triphenyl­arsine)copper(I) hexa­fluoridophosphate

In the crystal structure of the title compound, [Cu(C18H15As)4]PF6, the Cu atom is coordinated by four As atoms of triphenyl­arsine ligands in a tetra­hedral geometry. The complex cation is located on a crystallographic threefold axis. Both PF6 − anions are located on special positions of site symmetry . The Cu—As bond of the independent arsine ligand is shorter than the Cu—As bonds of the three symmetry-related arsine ligands

Photochemistry and Photophysics of Antimony(III) Hyper Porphyrins: Activation of Dioxygen Induced by a Reactive sp Excited State

Observations of the photoredox reactivity of antimony(III) porphyrin complexes are reported. Upon irradiation with visible light under ambient conditions, a photooxidation to the corresponding dihydroxoantimony(V) porphyrins occurs. At the same time a two-electron or four-electron reduction of molecular oxygen takes place, depending on the experimental conditions. In the absence of suitable electron acceptors, a photoinduced disproportionation reaction occurs. The photolysis of antimony(III) porphyrins shows a pronounced wavelength dependence. The reactive excited state is concluded to be of the metal-centered sp type. An extended model for the electronic structure of p-type hyper metalloporphyrins is suggested

Functionalized derivatives of 1,4-dimethylnaphthalene as precursors for biomedical applications: synthesis, structures, spectroscopy and photochemical activation in the presence of dioxygen

Decomposition of endoperoxide containing molecules is an attractive approach for the delayed release of singlet oxygen under mild reaction conditions. Here we describe a new method for the adaptation of the corresponding decay times by controlling the supramolecular functional structure of the surrounding matrix in the immediate vicinity of embedded singlet oxygen precursors. Thus, a significant prolongation of the lifetime of the endoperoxide species is possible by raising the energy barrier of the thermal (1)O(2)-releasing step via a restriction of the free volume of the applied carrier material. Enabling such a prolonged decomposition period is crucial for potential biomedical applications of endoperoxide containing molecules, since sufficient time for appropriate cell uptake and transport to the desired target region must be available under physiological conditions before the tissue damaging-power of the reactive oxygen species formed is completely exhausted. Two novel polyaromatic systems for the intermediate storage and transport of endoperoxides and the controlled release of singlet oxygen in the context of anticancer and antibiotic activity have been prepared and characterized. These compounds are based on functionalized derivatives of the 1,4-dimethylnaphthalene family which are readily forming metastable endoperoxide species in the presence of dioxygen, a photosensitizer molecule such as methylene blue and visible light. In contrast to previously known systems of similar photoreactivity, the endoperoxide carrying molecules have been designed with optimized molecular properties in terms of potential chemotherapeutic applications. These include modifications of polarity to improve their incorporation into various biocompatible carrier materials, the introduction of hydrogen bonding motifs to additionally influence the endoperoxide decay kinetics, and the synthesis of bifunctional derivatives to enable synergistic effects of multiple singlet oxygen binding sites with an enhanced local concentration of reactive species. With these compounds, a promising degree of endoperoxide stability adjustment within the carrier matrix has been achieved (polymer films or nanoparticles), which now opens the stage for appropriate targeting of the corresponding pro-drugs into live cells. First results on cytocidal and cytostatic properties of these compounds embedded in ethylcellulose nanoparticles are presented. Furthermore, an efficient low-cost method for the photochemical production of reactive endoperoxides based on high-power 660 nm LED excitation at room temperature and ambient conditions in ethanol solution is reported

The First Successfully Synthesized and Characterized Indium Corrole: Tris(pentafluorophenyl)corrolatoindium(III)

Corroles are deeply coloured tetrapyrrole compounds with a conjugated 18π-electron aromatic ring system carrying one direct pyrrole–pyrrole linkage. Many metal complexes of corrole ligands have been successfully synthesized in the last decades, and both their molecular as well as their electrochemical and photophysical properties have been investigated. Although several metallocorroles with group 13 elements (B, Al and Ga) are very well characterized, attempts to investigate the corresponding corrole complexes of the heavier elements of this main group are still quite rare. Especially the synthesis of a stable indium corrole molecule has been tried many times, but until today these compounds have not been obtained successfully to be characterized properly. In this work, the preparation and characterization of stable 5,10,15-tris(pentafluorophenyl)corrolatoindium(III) derivatives has been achieved. These new indium corrole complexes obtained were fully and successfully characterized by relevant analytical techniques (NMR, HR-MS, UV-Vis, Fluorescence and FTIR), and their photophysical and electrochemical features were studied and investigated for the first time

Suppressing Effect of 2-Nitrobenzaldehyde on Singlet Oxygen Generation, Fatty Acid Photooxidation, and Dye-Sensitizer Degradation

2-Nitrobenzaldehyde was found to efficiently block singlet oxygen generation in a series of different test samples upon exposure to UV and visible light under aerobic conditions. The effect of quenching singlet oxygen formation was monitored in the presence of 1, 4-diazabicyclo [2.2.2] octane (DABCO) acting as a well-known singlet oxygen scavenger. A comparison of different nitrobenzaldehyde isomers with other highly effective synthetic antioxidants used in the food industry such as butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), tert-butylhydroquinone (TBHQ) revealed that the protection of materials from singlet oxygen decreases in the order of 2-nitrobenzaldehyde > DABCO > TBHQ > 3-nitrobenzaldehyde > BHA > 4-nitrobenzaldehyde > BHT. Upon addition of 2-nitrobenzaldehyde, the oxidation of fatty acids and the degradation of photosensitizers was found to be considerably diminished, which indicates that the presence of 2-nitrobenzaldehyde has a significant protective influence by restricting the singlet oxygen generation and photodegradation of dyes. Moreover, the compound turned out to display its highly suppressing effects on typical singlet oxygen-dependent reactions, such as fatty acid photooxidation and dye photosensitizer degradation, in a rather broad spectral region covering wavelengths from 300 nm (UV-B) to 575 nm (close to the maximum of ambient solar radiation).(VLID)341213