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The asymmetric unit of the title compound, C25H18N6.H2O, comproses two molecules (I and II), together with a water molecule. The terminal phenyl groups attached to the methyl groups of the molecules I and II do not overlap completely, but are approximately perpendicular. In the crystal, the molecules are connected by N--H...N, C--H...N, O--H...N and N--H...O hydrogen bonds with each other directly and through water molecules, forming layers parallel to the (001) plane. C--H...π interactions between these layers ensure the cohesion of the crystal structure. A Hirshfeld surface analysis indicates that H...H (39.1% for molecule I; 40.0% for molecule II), C...H/H...C (26.6% for molecule I and 25.8% for molecule II) and N...H/H...N (24.3% for molecules I and II) interactions are the most important contributors to the crystal packing. [ABSTRACT FROM AUTHOR]

Selective conversion of methanol to C2-C4 alkenes and p-xylene is one of the appealing chemical routes. Currently, there are no effective catalysts for the co-production of C2-C4 alkenes and p-xylene from methanol. To date, modified medium-pore ZSM-5 zeolites are considered one of the excellent candidates for the development of selective catalysts for the conversion of methanol to lower alkenes and aromatic hydrocarbons. In this paper, nanosized (30-33nm) powders of Ho2Mg1-xAl2O4 spinel structure were obtained by the method of combustion of nitrate solutions of aluminium, magnesium, holmium, diethylmalonate and hydrazine monohydrate with the further calcination of nanopowders at 1000 °C. Obtained nanopowders used in the preparation of a solid-phase catalytic composition of HoxMg1-xAl2O4-HZSM-5. Various physico-chemical properties of the catalytic composition were investigated using X-ray diffraction (XRD), pyridine adsorption (BİO-RAD FTS 3000 MX) and low-temperature nitrogen adsorption (BET) techniques. The textural properties and acidity of the catalysts were altered by adjusting the nanopowder concentration (1.0-5.0 wt.%) in the catalytic composition. The conversion of methanol in the presence of the catalytic compositions was carried out in flow-type fixed-bed catalytic reactor at 400 °C, in the presence of nitrogen carrier gas with 1.0 h-1 flow rate. A correlation between the selectivity to C2-C4 alkenes and p-xylene with a ratio of Lewis (L) and Brønsted (B) acid sites and the volume of the catalyst pore, the amount of the modifier in the catalytic system has been established. As the amount of HoxMg1-xAl2O4 nanopowder increases, the ratio of B/L acid sites and the volume of the catalyst pore decrease, which play a significant role in the increase of the selectivity to C2-C4 alkenes and p-xylene. Maximum yield of C2-C4 alkenes (31.6%) and selectivity to p-xylene (80.5%) is achieved on a catalytic composition containing 5.0 wt.% HoxMg1-xAl2O4. [ABSTRACT FROM AUTHOR]