Comparative study of the catalytic activity of a series of β-brominated Mn–porphyrins in the oxidation of olefins and organic sulfides: Better catalytic performance of the partially brominated ones

An octabrominated Sn(iv) tetraisopropylporphyrin as a photosensitizer dye for singlet oxygen biomedical applications

Two novel Sn(iv) tetraisopropylphenylporphyrins have been synthesized to explore the effect of octabromination at the β-pyrrole positions on their photophysical properties and photodynamic activity. The lower energy Q band of an octabrominated complex lies at 675 nm well within the therapeutic window. The octabrominated dye has a relatively high singlet oxygen quantum yield of 0.78 in DMF and exhibits favorable photodynamic activity against MCF-7 cells with an IC50 value of 10.7 μM and a 5.74 log reduction value (5 μM) towards S. aureus under illumination at 660 nm for 60 min with a Thorlabs M660L3 LED (280 mW cm-2).

Rational Synthesis of 2-Bromoporphyrins and 2,12-Dibromoporphyrins

Bromoporphyrins were prepared by the metal-mediated self-condensation of brominated 1-formyldipyrromethanes. Depending on the conditions, Mg(II)-2,12-dibromoporphyrin and Mg(II)-2-bromoporphyrin could be obtained in up to 11% and 17% isolated yield, respectively. Zn(II) was also a viable templating metal. The positions of the bromine substituents were confirmed by 2D-NMR spectroscopic analysis and the X-ray crystal structure of a derivative. Suzuki and Sonogashira reactions of the bromoporphyrins yielded 2-substituted or 2,12-disubstituted porphyrins with red-shifted absorption and emission spectra. This method provides access to the minimalist core of β-mono- and β,β'-disubstituted porphyrins from readily available starting materials.

Bioinspired versus Enzymatic Oxidation of Some Homologous Thionine Dyes in the Presence of Immobilized Metalloporphyrin Catalysts and Ligninolytic Enzymes

Thionines are recalcitrant and polluting textile dyes presenting various degrees of N-methylation. In this paper, a complete series of homologous thionines was used as the substrates for oxidation in the presence of a bioinspired commercial iron-porphyrin immobilized on to imidazole- and pyridine-functionalized fumed silica, to emulate the active site of ligninolytic peroxidases. The obtained catalytic adducts showed a remarkable ability to catalyze thionine dye oxidation in the presence of different oxidants such as potassium monopersulfate and hydrogen peroxide. Different oxidation patterns were obtained and mechanistically discussed, in comparison with those observed in the presence of some ligninolytic oxidizing enzymes.

Ultrasound promoted preparation of Mn(III)-porphyrin nanoparticles: An efficient heterogeneous catalyst for oxidation of alkenes, alkanes and sulfides

In the present research meso-tetrakis(4-carboxyphenyl)porphyrinatomanganese(III) acetate (Mn(TCPP)OAc) nanoparticles have been prepared for the first time without any stabilizing agent or supporting matrix under ultrasonic irradiation. Scanning electron microscopy (SEM) was used to characterize and investigate the nanocatalyst. Rapid, efficient, facile and highly selective oxidation of a wide range of olefins by tetra-[Formula: see text]-butylammonium hydrogen monopersulfate over the prepared manganese nanocatalyst was investigated. Also oxidation of sulfides and alkanes in the presence of the (Mn(TCPP)OAc) nanoparticles were studied. The catalyst is recovered by filtration and reused at least five times.

Crystal structure, magnetic and catalytic oxidation properties of manganese(iii) tetrakis(ethoxycarbonyl)porphyrin

5,10,15,20-tetrakis(ethoxycarbonyl)porphyrin manganese(iii) chloride (Mn^IIITECPCl) existed as a Mn–O coordinated dimer. Mn^IIITECPCl gave high yield in oxidation of styrene by using TBHP or PhIO oxidant and was found recyclable.