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A series of 5,10,15,20‐tetrakis(2,3‐dichlorophenyl)porphyrinate complexes of manganese(III) [MnIII(T2,3DCPP)X] with six different axial ligands (X=NO3−, AcO−, IO3−, Br−, Cl−, HO−) were investigated as catalysts in the cycloaddition reactions of CO2 and styrene oxide (SO), under mild conditions, i. e., atmospheric pressure and 60 °C. [MnIIIT(2,3DCPP)IO3] showed the best catalytic performance, selectively producing the respective cyclic carbonate from diverse epoxides using tetrabutylammonium bromide as a nucleophile source. Mechanistic considerations were inferred from electronic spectra and spectrophotometric titrations, showing that there are a series of equilibriums involved in the formation of the catalytic active species. Stability constants for the proposed equilibrium models were determined using SQUAD software. A catalytic cycle has been proposed based on those observations.

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We demonstrate that hybrid systems of porphyrins and chirality enriched (6,5) single-walled carbon nanotubes (E-SWCNTs) are better candidates for photodynamic therapy (PDT) than their components alone. Surprisingly, the E-SWCNTs act as optical absorption enhancers to the porphyrins increasing the oxygen singlet production when illuminated by a light source with energy higher than the E-SWCNT gap plus the equivalent in energy of an E-SWCNT phonon. The phenomenon is explained based on energy transfer from the E-SWCNT to the porphyrin which finally transfers it to the oxygen molecule. The large optical absorption cross section of E-SWCNT and the resonance of the porphyrin to the oxygen singlet–triplet transition are responsible for the synergistic effect.

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