溶胶-凝胶法制备V2O5微晶及其合成活化能研究

以NH4VO3和CO( NH2)2等为起始原料,采用溶胶-凝胶法制备了V2O5微晶.研究了煅烧温度对产物物相和显微结构的影响,以及反应的合成活化能.采用X射线衍射、扫描电镜等手段对产物进行了表征.结果表明,后处理温度为500℃可得到V2O5微晶,当反应温度超过600℃时,V2O5微晶表现出(001)晶面的取向生长特征.通过差热分析,计算得到其合成活化能为95.81 kJ/mol.     

Synthesis and Crystal Structure of E,E-1,4-Bis[4＇-(N,N-di-n-butylamino)-styryl]-2,5-dimenthoxybenzene

The title compound E,E-1,4-bis[4＇-(N,N-di-n-butylamino)styryl]-2,5-dimen- thoxybenzene (abbreviated to DBMB) has been synthesized by the wittig reaction of [(2,5- dimethoxy-1,4-phenylene)]bis(methylene)]bistriphenylphosphonium dichloride with 4-(N,N-di-n- butylamino)benzaldehyde. Its crystal structure was determined by a four-circle diffractometer. Crystal data: C40H56N2O2, Mr = 596.87, triclinic, space group P, a = 0.9303(2), b = 0.9625(2), c = 1.0442(2) nm, α = 81.493(12), β = 78.387(12), γ = 87.876(11)°, V = 0.9057(4) nm3, Z = 1, Dc = 1.094 g/cm3, F(000) = 326, μ(MoKa) = 0.066 mm-1, the final R = 0.0925 and wR = 0.2092. The results reveal that the molecule is a completely reverse structure with fine symmetry and a conju- gated system.     

A green,efficient and recoverable CeO2/MWCNT nanocomposite catalyzed click synthesis of pyridine-3-carboxamides

A facile, green and environmentally-friendly protocol for the preparation of ceria doped multi-walled carbon nanotubes (2.5%CeO₂/MWCNTs) composite catalysts are developed. The synthesized catalyst materials have been characterized by using P-XRD, SEM, TEM and BET analysis. Further, the composite was utilized as a highly efficient and reusable heterogeneous nano-catalyst for the synthesis of pyridine-3-carboxamide derivatives by multicomponent condensation of acetoacetanilide, ammonium acetate, substituted aromatic aldehyde and ethyl cyanoacetate via one-pot reaction under ethanol solvent conditions at R.T. The remarkable advantages of this green protocol exhibits operational simplicity, easy workup procedure, inexpensive, evading of toxic solvents, shorter reaction times (≤ 15 mins), excellent yields and also avoidance of column chromatography. Furthermore, the catalyst was recyclable and reusability endured for a minimum of six consecutive cycles without significant loss in the catalytic activity.     

Synthesis and Structure of a 3D Manganese Coordination Polymer with 1,3-Bis（benzimidazol-1-ylmethyl）-2,4,6-trimethylbenzene and 1,5-Naphthalenedisulfonate

The organic-inorganic hybrid polymer [Mn(mbbimb)2(1,5-nds)]n 1 has been synthesized using 1,5-naphthalenedisulfonate (1,5-nds) and 1,3-bis(benzimidazol-1-ylmethyl)- 2,4, 6-trimethylbenzene (mbbimb) with Mn(OAC)2·4H2O in solvothermal reaction. The X-ray crystal structure analysis indicates that 1 crystallizes in monoclinic, space group C2/c with a = 21.3546(17), b = 11.8841(7), c = 22.1588(16) , β = 108.058(3)°, C60H54MnN8O6S2, Mr = 1102.17, Ζ = 4, V = 5346.5(7) 3, Dc = 1.369 g/cm3, μ = 0.386 mm-1, F(000) = 2300, S = 1.091, R = 0.0634 and wR = 0.1559 for 4641 observed reflections (I > 2σ(I)). The Mn center is six-coordinated to furnish a distorted octahedral geometry, and the overall framework is a 6-con- nected 3D net.     

Crystal Structure of a Threedimensional Coordination Polymer {[Ca3(μ5-OOCCH2OCH2COO)3(H2O)4]·4H2O}n

A novel three-dimensional coordination polymer, {[Ca3(μ5-OOCCH2OCH2COO)3(H2O)4]·4H2O}n, has been synthesized with oxydiacetate as bridge ligand and structurally determined by X-ray crystallography. The crystal belongs to monoclinic, space group C2/c with a = 17.805(2), b = 9.3923(12), c = 17.255(2)(A), β = 107.838(5)°, V = 2746.8(6) (A)3, Mr = 660.58, C12H28Ca3O23, Dc = 1.597 g/cm3, μ = 0.695 mm-1, Z = 4, F(000) = 1376, GOOF = 1.027, R = 0.0303 and wR = 0.0660. In the complex there are two coordination modes for Ca(Ⅱ) ions, one coordinated by three μ5-OOCCH2OCH2COO2- bridge ligands together with two H2O molecules, and the other by five μ5-OOCCH2OCH2COO2- bridge ligands. In both coordination modes each Ca(Ⅱ) ion assumes a distorted dipentapyramidal CaO7 geometry; whereas each oxydiacetate is coordinated with five Ca(Ⅱ) ions and acts as a pentdentates bridge ligand.     

Synthesis and Crystal Structure of 4-（4-Bromophenyl）- 3,4-dihydro-6-methyl quinolin-2（1H）-one

The title compound (C16H14BrNO) has been synthesized by the reaction of p-tolylamine, Meldrum’s acid and 4-bromo-benzaldehyde, and its structure was characterized by IR, 1H NMR and X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P21/n with a = 7.6850(11), b = 8.3004(11), c = 21.301(3) , β = 95.110(2)°, V = 1353.4(3) 3, Mr = 316.19, Z = 4, Dc = 1.552 g/cm3, μ(MoKα) = 3.028 mm-1, F(000) = 640, the final R = 0.0345 and wR = 0.0768. X-ray analysis reveals that the atoms of C(1), C(2), C(3), C(4), C(5) and N(1) form a six-membered ring of boat conformation.     

Synthesis and Structural Characterization of a Supramolecular Compound [(C8H9NO2)·HgI2]n Constructed from Hg…I and C-H…O Linkage

The title complex [(C8H9NO2)·HgI2]n has been synthesized from the reaction of pyridine-3-ethylformate with mercury iodide in the mixture of DMF and absolute methanol. Its structure was determined by IR, elemental analysis and X-ray single-crystal diffraction analysis. The crystal is of monoclinic system, space group P21/n with a = 4.3397(5), b = 25.051(3), c = 12.3719(13) (A)3, β = 92.2130(10)°, C8H9HgI2NO2, Mr = 605.55, V = 1344.0(3) (A)3, Z = 4, Dc = 2.993 mg·m-3, F(000) = 1064, μ = 16.024 mm-1, the final R = 0.0258 and wR = 0.0504. In the title complex, the center Hg(Ⅱ) exhibits a four-coordinated distorted tetrahedral geometry. A three-dimensional network arrangement is presented via Hg…I weak interactions among adjacent molecules.     

Synthesis and Crystal Structure of (E)-Ethyl 3-Keto-18β-glycyrrhetinate 3-Oxime

A novel derivative of glycyrrhetinic acid, (E)-ethyl 3-keto-18β-glycyrrhetinate 3- oxime C32H49NO4 (Mr = 511.72), was synthesized and structurally characterized by IR, 1H NMR and single-crystal X-ray diffraction. It belongs to monoclinic, space group P21, with a = 12.4897(12), b = 7.3190(7), c = 15.9944(14) , β = 94.833(2)o, V = 1456.9(2) 3, Z = 2, Dc = 1.167 g/cm3, μ = 0.075 mm-1, F(000) = 560, the final R = 0.0449 and wR = 0.1122. A total of 7486 reflections were collected, of which 2785 were independent (Rint = 0.0199) and 2605 were observed with I > 2σ(I). There exists an intermolecular hydrogen bond which helps to stabilize the crystal structure.     

Crystal Structure and Conformation of an Imino Sugar

The title compound 3 was synthesized and characterized by IR,NMR and H-RMS,and its crystal structure was determined by X-ray diffraction analysis. The crystal is of monoclinic system (C16H23NO7S,Mr=373.41),space group P21,with a=12.000(2),b=5.5970(11),c=13.689(3),β=93.25(3)°,V=917.9(3)3,Z=2,Dc=1.351 g/cm3,F(000)=396,μ=0.213 mm-1,the final R=0.0489 and wR=0.0777 for observed reflections (I > 2σ(I)). Three intramolecular and three intermolecular hydrogen bonds were found. The absolute configuration of this molecule was confirmed by comparing with the original material.     

Effect of Extract and Synthesized Derivatives of Isolated Compound from Symplocos chinensis f. Pilosa Ohwi on Neuropathic Pain in Mice

Neuropathic pain is described as the “most terrible of all tortures that a nerve wound may inflict.” The aim of the present study was to demonstrate the antinociceptive effect of Symplocos chinensis f. pilosa Ohwi water extract (SCW) and synthesized derivatives of the isolated compound. The antinociceptive effect was tested using the acetic acid-induced writhing and 5% formalin tests. Antinociceptive effects on neuropathic pain were evaluated using the von Frey test with chronic constriction injury (CCI) and surgical nerve injury (SNI) models and tail-flick test with a vincristine-induced pain model. An Ames test was also conducted. 5-hydroxymethylfurfural (5-HMF) was isolated and derivatives were synthesized with various acid groups. Among the plant water extracts, SCW showed significantly effective activity. Additionally, SCW presented antinociceptive effects in the neuropathic pain models. The SCW water fraction resulted in fewer writhes than the other fractions, and isolated 5-HMF was identified as an effective compound. Because 5-HMF revealed a positive response in the Ames test, derivatives were synthesized. Among the synthesized derivations, 5-succinoxymethylfurfural (5-SMF) showed the best effect in the neuropathic pain model. Our data suggest that SCW and the synthesized compound, 5-SMF, possess effective antinociceptive activity against neuropathic pain.