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A series of water‐insoluble iron(III) and manganese(III) porphyrins, FeT(2‐CH3)PPCl, FeT(4‐OCH3)PPCl, FeT(2‐Cl)PPCl, FeTPPCl, MnT(2‐CH3)PPOAc, MnT(4‐OCH3)PPOAc, MnT(2‐Cl)PPOAc and MnTPPOAc, in the presence of imidazole (ImH), F−, Cl−, Br− and acetate were used as catalysts for the aqueous‐phase heterogeneous oxidation of styrenes to the corresponding epoxides and aldehydes with sodium periodate. Also, the effect of various reaction parameters such as reaction time, molar ratio of catalyst to axial base, type of axial base, molar ratio of olefin to oxidant and nature of metal centre on the activity and oxidative stability of the catalysts and the product selectivity was investigated. Higher catalytic activities were found for the iron complexes. Interestingly, the selectivity towards the formation of epoxide and aldehyde (or acetophenone) was significantly influenced by the type of axial base. Furthermore, Br− and ImH were found to be the most efficient co‐catalysts for the oxidation of olefins performed in the presence of the manganese and iron porphyrins, respectively. The optimized molar ratio of catalyst to axial base was different for various axial bases. Also, the order of co‐catalyst activity of the axial bases obtained in aqueous medium was different from that reported for organic solvents. The use of a convenient axial base under optimum reaction catalyst to co‐catalyst molar ratio in the presence of the manganese porphyrin gave the oxidative products with a conversion of ca 100% in a reaction time of less than 3 h. However, the catalytic activity of the iron porphyrins could not be effectively improved by increasing the catalyst to co‐catalyst molar ratio.

A highly efficient and simple method for the synthesis of N-aryl derivatives of pyrimidine and purine nucleobases via Narylation of nucleobases using zinc oxide in 1-butyl-3-methylimidazolium bromide ([bmim]Br) under microwave as well as thermal conditions is described. In both conditions, the title compounds were produced in high to excellent yields and in short reaction times.

An azo dye, Reactive Black 5 (RB5), was degraded by three photocatalysts of g‐C3N4, Ag(2 %)/g‐C3N4, and Ag(5 %)/g‐C3N4 with the specific surface areas of 34.41, 28.70, and 35.58 m2 g−1 and the band gaps of 2.52, 1.56, and 1.71 eV under sunlight illumination, respectively. The results showed 40 mg/L of g‐C3N4 could degrade completely 10 ppm RB5 at pH 3.4 within 10 min under sunlight irradiation with the first‐order rate constant of 0.312 min−1. Under the same conditions, the complete degradation time of RB5 reduced to 5 and 7 min when the plasmonic nanocomposites of Ag (2 %)/g‐C3N4 and Ag (5 %)/g‐C3N4 were used as photocatalysts, respectively. Ag content had an important influence on the photocatalytic activity of g‐C3N4 against RB5 so that Ag (2 %)/g‐C3N4 possessed the best photocatalytic efficiency with the rate constant of 0.795 min−1. In fact, Ag nanoparticles through the surface plasmon resonance effects and by accepting the photogenerated electrons could improve the visible‐light absorption and increase charge separation of g‐C3N4. The results showed superoxide radical is the main oxidant in the photodegradation of RB5.