The photocatalytic activity of Fe/ZnO/SiO 2 catalysts under visible-light irradiation for the degradation of methylene blue was evaluated. The effect of pH, illumination time, amount of catalyst loaded, and initial dye concentration on the degradation efficiency of methylene blue was investigated. The results reveal that the optimum photocatalytic oxidation conditions of methylene blue are as follows: pH = 4 and illumination time is 30 min, the amount of catalyst loading is 0.075 g/L and 50 ppm methylene blue dye concentration. Under these conditions, the removal efficiency of methylene blue was 100%.

We describe the modular synthesis and characterization of several substituted N-hetero benzenacyclooctaphanes (BAOs), a new motif for heteroaromatic conjugated macrocycles. The targets were synthesized via condensation of substituted aromatic ortho-diamines with a cyclic octaketone building block in moderate to excellent yields (41-91 %). We evaluated the optical and electronic properties and the solid-state structures of the targets and discuss their properties through comparison with their linear diphenyl N-heteroacene counterparts.

Porous organic polymers (POPs) incorporating macrocyclic units have been investigated in recent years in an effort to transfer macrocycles’ intrinsic host-guest properties onto the porous networks to achieve complex separations. In this regard, highly interesting building blocks are presented by the family of cyclotetrabenzoin macrocycles with rigid, well-defined, electron-deficient cavities. This macrocycle shows high affinity towards linear guest molecules such as carbon dioxide, thus offering an ideal building block for the synthesis of CO2-philic POPs. Herein, we report the synthesis of a porous organic polymer through the condensation reaction between cyclotetrabenzil with 1,2,4,5-tetraaminobenzene under ionothermal conditions using the eutectic zinc chloride/sodium chloride/potassium chloride salt mixture at 250 oC. Notably, following the condensation reaction, the macrocycle favors 3D growth rather than 2D one while retaining the cavity. The resulting polymer, named 3D-mPOP, showed a highly microporous structure with the BET surface area of 1142 m2 g−1 and a high carbon dioxide affinity with a binding enthalpy of 39 kJ mol−1. Moreover, 3D-mPOP showed very high selectivity for carbon dioxide in carbon dioxide/methane and carbon dioxide /nitrogen mixtures.

Benzoin condensation is one of the oldest rigorously described organic reactions, having been discovered in 1832 by Liebig and Wöhler. This Feature Article summarizes our work on cyclobenzoins: a class of macrocyclic compounds prepared by a benzoin cyclooligomerization of simple aromatic dialdehydes.

The ZnO-SiO 2 xerogel photocatalyst was prepared via the sol-gel technique and applied for photodegradation of methylene blue (MB) dye. The optimum conditions for preparation of ZnO-SiO 2 gel is 30:70 ZnO:SiO 2 molar ratio and TEOS:C 2 H 5 OH:H 2 O:HNO 3 is 1:16:12:0.04 molar ratios at 30°C for 30 min, at these conditions the photoactivity of ZnO-SiO 2 xerogel was 99% at a surface area of 500 m 2 /g after 60 min. The optimum loading of ZnO-SiO 2 photocatalyst was 0.050 wt% that gives 99% MB dye removal efficiency after 40 min. The overall kinetics of photodegradation of MB dye using ZnO-SiO 2 photocatalyst was found to be of the first order.

Three tridentate Schiff base ligands were synthesized from the reactions between 2-picolylamine and salicylaldehyde derivatives (3-ethoxy (OEt), 4-diethylamino (NEt2) and 4-hydroxy (OH)).

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Reduction of cyclotribenzoin with sodium borohydride produces a cone-shaped hexaol. Crystals of this hexaol, obtained from wet tetrahydrofuran, encapsulate clusters of five water molecules in an idealized hydrogen-bonded arrangement. The water pentamer is stabilized by hydrogen bonding with the -OH groups of the hexaol, and [O-H⋅⋅⋅π] interactions with the benzene rings of the reduced cyclotribenzoin.