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Single crystal X-ray analysis of a 1 : 2 complex between the dinaphthopyridino-l8-crown-6 host (1) and acetonitrile is reported. Crystals of the complex are monoclinic,P21/c witha = 12.178(5),b = 8.186(1),c = 30.873(1) Å, = 96.86(1)°, andD c = 1.25 g cm–3 forZ = 4. The host molecule reveals an approximate mirror symmetry and exists in a so-called dentist's chair conformation. One of the acetonitrile guest molecules is involved in possible weak interactions to two oxygen atoms of the host macroring, while the other fills free lattice space only.  相似文献   
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Research on Chemical Intermediates - This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/10.1007/s11164-020-04374-7  相似文献   
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The crystal structure of the title compound, [CoCl(C18H37N4O2){ZnCl3}], has been determined by X‐ray diffraction.Cmeso‐5,5,7,12,12,14‐Hexa­methyl‐1,4,8,11‐tetra­aza­cyclotetradecane‐N‐acetate acts as a bridging ligand to coodinate with CoIII and ZnII ions. The CoIII ion is six‐coordinate in a nearly octahedral environment provided by one Cl atom, four N atoms of the bridging ligand, and one O atom. The ZnII ion is four‐coordinate in a distorted tetrahedral environment completed by three Cl atoms and an O atom of the bridging ligand.  相似文献   
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Bubbling acetyl­ene gas slowly through a methanol solution of [(CO)6Fe2{μ‐SSe}] containing sodium acetate for 48 h at room temperature yields the double‐butterfly complex μ‐[ethane‐1,1,2,2‐tetra(selenido/sulfido)]bis[hexacarbonyldiiron(FeFe)], [Fe4(C2H2S2Se2)(CO)12]. The molecular structure was established by single‐crystal X‐ray diffraction techniques. The structure consists of two Fe2SSe butterfly units linked to each other through a bridging HC—CH group. The mol­ecule has twofold symmetry and the two Fe atoms have distorted octahedral geometries.  相似文献   
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An aerobic oxidative cross-dehydrogenative coupling reaction between sp(3) C-H and sp(2) C-H bonds is developed by employing a vanadium catalyst (10 mol%) in an aqueous medium using molecular oxygen as the oxidant. This environmentally benign strategy exhibits larger substrate scope and shows high regioselectivity.  相似文献   
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Nanosized platinum particles loaded on the TiO2 nanoparticles were prepared to assess its photocatalytic activity in simple one-pot synthesis of quinaldines from anilines in ethanol using UV light. The catalyst was characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy, X-ray photoelectron spectra (XPS), Brunauer?CEmmer?CTeller surface area, atomic force microscope and diffuse reflectance spectra. XRD patterns revealed that the crystal structure of Pt?CTiO2 resembled anatase phase of TiO2. The UV?CVis spectra indicated an increase in absorption of visible light when compared to TiO2. XPS analysis reveals that platinum particles are present mainly in metallic form. Furthermore, TEM analysis showed non-spherical-shaped Pt?CTiO2 nanoparticles of the diameter 10?C30?nm. Upon irradiation in the presence of Pt?CTiO2, aniline and oxidation products derived from ethanol undergo condensation?Ccyclization to afford quinaldines. Higher efficiency of Pt?CTiO2 than Au?CTiO2 in the conversion of aniline to quinaldines is due to the higher work function of Pt.  相似文献   
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Photocatalysis has recently been regarded as one of the most viable technologies for water treatment. Scholars all over the world are focusing on nanocomposites for water treatment for efficient and effective sanitization of bodies of water. Because of their high surface area, high chemical reactivity, excellent mechanical strength, low cost, and nanoscale composite materials have enormous potential to purify water in a various way. In this study, n-type TiO2 was synthesized and tailored to produce a TiO2/BiOI n–p nanocatalyst for enhanced photodegradation of 2,4-dinitrophenol (2,4-DNP) under UV-A and solar light respectively. Because of the formation of a heterojunction between BiOI and TiO2, the photocatalytic activity in TiO2/BiOI absorbs strongly in both the UV and visible regions and it has a lower recombination rate of the e-/h+ pairs. Furthermore, the generation of OH?, O2?– radicals during the oxidation process is attributed to the photodegradation of 2,4-DNP. The results revealed that the TiO2/BiOI manifest outperformed BiOI and TiO2 in terms of photocatalytic function. XRD, BET, HR-SEM-EDX with ECM, HR-TEM, FT-IR, PL, and UV-DRS techniques determined the photocatalyst composition. The HR-SEM images clearly showed that the particles are less than 27 ?nm in size. Thus, nanocomposite materials have played an important role in water purification.  相似文献   
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