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1.
采用密度泛函理论中的广义梯度近似(DFT/GGA)方法, 在PW91/DNP 水平上研究了4,7-二(2-噻吩基)苯并噻二唑-3-辛基噻吩二炔在PdCl2(PPh3)2 催化下的合成机理. 优化了反应过程中的反应物、中间体、过渡态和产物, 通过能量分析结果证实了中间体和过渡态的真实. 在同样的方法和精度研究了4,7-二(2-噻吩基)苯并噻二唑-3-辛基噻吩二炔在没有催化剂下的合成机理. 通过计算结果得到此反应在有PdCl2(PPh3)2 催化情况下的活化能小于没有催化剂情况下的活化能, 从而证明了PdCl2(PPh3)2 催化剂的催化活性. 采用密度泛函理论与周期性平板模型相结合的方法, 研究了产物P 在TiO2(100)表面的吸附, 通过Mulliken charge 和前线轨道分析表明: 当P 吸附在TiO2(100)表面时, P 向TiO2(100)表面转移0.692 e 电荷, 前线轨道能隙变窄. 理论预测的结果与实验值吻合.  相似文献   

2.
In order to continue our studies on the synthesis, properties and coordination of s-tetrazine, 3,6-di-(pyridin-3-yl)-s-tetrazine (II, 3-dptz) was synthesized and characterized by 1H- NMR, MS and IR spectra. And the coordination reaction of 3-dptz with nitrate of Cu(II) was studied. 3-dptz reacting with CuII salt [Cu(NO3)2·2H2O] generates a new salt, nitrate of 2,5-di-(pyridin-3- yl)-1,3,4-oxadiazolene (III). III was determined by IR spectra and single-crystal X-ray diffraction to give the following crystal data: space group P21/c, a = 4.9112(1), b = 8.4101(3), c = 29.499(1) , β = 93.266(2)o, V = 1216.44(7) nm3, Mr = 287.24, Z = 4, Dc = 1.568 g/cm3,μ= 0.122 mm-1, F(000) = 592, R = 0.0430 and wR = 0.1240. The results show that III is composed of one cation and one nitrate anion. The cation consists of one H+ and one 2,5-di-(pyridin-3-yl)-1,3,4-oxadiazol molecule, with the former being attached to the latter via electrovalent bond with N3 atom. And the O(42) atom in the nitrate anion is disordered. Intra- and intermolecular H-bonds are observed in the crystal of the title compound. The mechanism of metal-assisted decomposition was also discussed briefly.  相似文献   

3.
《结构化学》2004,23(4):358-360
1INTRODUCTION4H-Chromeneisaconstructionunitofsomenaturalproducts.4H-Chromeneswithaminoandcyanogroupsarealsosynthonofsomespecialnaturalproducts[1,2].Thesubstituted4H-chromenespossessawiderangeofpharmacologicalactivi-ties[3~5].Inordertoinvestigatetheactivi…  相似文献   

4.
1 INTRODUCTION Schiff bases can be conveniently prepared from the corresponding aldehyde and primary amine, which, as multidentate ligands, have already received great attention. Many metal complexes of this kind of ligands have been used successfully in various re- actions, such as Diels-Alder and hetero-Diels-Alder reactions[1], kinetic resolution of racemic epoxides[2], and Nozaki-Hiyama-Kishi (NHK) reaction[3]. Recen- tly Berkessel et al. have reported that the Cr- complex of sal…  相似文献   

5.
The title compound 1-(4-chlorophenyl)-3-[5-(pyrid-4-yl)-1,3,4-thiadiazol-2-yl]urea (C14H10ClN5OS, Mr = 331.79) has been synthesized by the reaction of 2-amino-5-(pyrid-4-yl)- 1,3,4-thiadiazole with 4-chlorobenzoyl azide, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to triclinic system, space group P with a = 5.8550(8), b = 7.5668(10), c = 16.416(2) , α = 78.364(2), β = 81.204(2), γ = 84.749(2)°, V = 702.58(16) 3, Z = 2, Dc = 1.568 g/cm3, μ = 0.429 mm-1, F(000) = 340, the final R = 0.0442 and wR = 0.1092 for 2001 observed reflections (I > 2σ(I)). X-ray diffraction analysis reveals that the title molecule is nearly planar. In the crystal structure, the molecules are linked by strong intermolecular N-H…N hydrogen bonds together with weak nonclassical intermolecular (C-H…Y, Y = N, O and Cl) hydrogen bonds and stacked through π-π interactions. The preliminary bioassay shows that the title compound exhibits good fungicidal activities against Rhizoctonia solani, Botrytis cinerea and Dothiorella gregaria.  相似文献   

6.
1 INTRODUCTION The catalytic asymmetric synthesis has been a challenging subject in organic synthesis. The deve- lopment of efficient enantioselective catalysts appli- cable to a wide range of carbon-carbon bond form- ing reactions represents a pivotal …  相似文献   

7.
The title compound C6H4(C7H5N2)2 was prepared by the condensation of o-phenylenediamine with o-phthalic acid and characterized by elemental analysis, IR, UV and ^1H NMR spectra, and its structure was determined by single-crystal X-ray diffraction,showing the compound molecule belongs to (72 point group. A ID chain structure was formed by the intermolecular hydrogen bonds (N(2)H…N(I)).  相似文献   

8.
一种新型低带隙共轭聚合物的合成及其光学性质   总被引:2,自引:0,他引:2  
刘中义  李彦军  黄鹏程 《化学学报》2008,66(8):999-1002
在钯催化剂作用下, 通过4,7-二(5-溴-2-噻吩基)[2,1,3]苯并噻二唑与2,5-二乙炔基-3-辛基噻吩的偶联反应, 合成了一种新的共轭高分子聚4,7-二(2-噻吩基)苯并噻二唑-3-辛基噻吩二炔(PTE-DTBT). 通过紫外可见吸收光谱及荧光光谱对其光学性质进行了研究. 紫外-可见吸收谱结果表明, PTE-DTBT的固体膜光学带隙为1.71 eV; 电化学测试其带隙为1.88 eV. TiO2/PTE-DTBT共混固体膜的荧光发射谱结果表明电子供体PTE-DTBT分子与电子受体TiO2分子间存在有效的电子转移.  相似文献   

9.
The title compound (C20H21N3O4, Mr = 367.40) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction. The crystal is of orthorhombic, space group P212121 with a = 7.5143(15), b = 13.901(3), c = 18.545(4) , V = 1937.1(7) 3, Z = 4, Dc = 1.260 g/cm3, μ = 0.089 mm-1, F(000) = 776, the final R = 0.0616 and wR = 0.0912. X-ray diffraction reveals that the molecule adopts an E configuration about the central C=N double bond. The intermolecular O–H…O hydrogen bond stabilizes the crystal structure by causing the formation of a supramolecular architecture.  相似文献   

10.
1INTRODUCTIONThiosemicarbazidespossessingNC=Sgroupareanessentialstructurefeatureresponsibleforvariousbiocidalproperties[1~7].Moreover,theyaretheconvenientandkeyintermediatesforthesyn-thesisofheterocycliccompoundssuchas1,3,4-thiadiazoles,1,2,4-triazoleand…  相似文献   

11.
1 INTRODUCTION The transition metal complexes with dmit ligand together with their derivatives have received signi- ficant attention due to their metallic-like electronic properties[1~8]. More recently, our researches show that they may be the new kind…  相似文献   

12.
The geometry, electronic structure, polarizability and hyperpolarizability of dye sensitizer 3,4-bis[1-(carboxymethyl)-3-indolyl]-1H-pyrrole-2,5-dione (BIMCOOH) were studied using density functional theory (DFT) with hybrid functional B3LYP, and the electronic absorption spectra were investigated using semi-empirical quantum chemical method ZINDO-1 and time-dependent DFT (TDDFT). The results of natural bond orbital suggest that the natural charges of the dione, indole, and acetic groups are about 0.15e, -0.29e, and 0.44e, respectively. The calculated isotropic polarizability, polarizability anisotropy invariant and hyperpolarizability are 305.4, 188.3, and 1155.4 a.u., respectively. The electronic absorption spectral features in visible and near-UV region were assigned to the π→π^* transition due to the qualitative agreement between the experiment and the TDDFT calculations, and the transitions of the excited states 9-11 related to photoinduced intramolecular charge transfer processes. The analysis of electronic structure and UV-Vis absorption indicates that the indole groups primarily contributed sensitization of photo-to-currency conversion processes, and the interracial electron transfer between semiconductor TiO2 electrode and dye sensitizer BIMCOOH are electron injection processes from excited states of the dyes to the semiconductor conduction band.  相似文献   

13.
1INTRODUCTIONTheSchiffbasesderivedfromb-diketonesandaliphaticamineshavebeenshowntoexistastheketo-amines.However,ifsubstituentseitherattheketooraminogrouparearomatic,itmaybeexpectedtheenoliminewillbethefavoredtautomericform[1].Recently,someSchiffbasesderivedfromTTA(4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione)andPMBPhavebeenstudiedbyWang[2]andYu[3]etal.Inordertostudytherelationshipbetweenthestructuresandperformancesofthesecompounds,thetitlecom-poundwillbereportedherein.2EXPERIMENT…  相似文献   

14.
The title compound, 5-N-i-propyl-2-(2′-nitrobenzenesulfonyl)-glutamine, was synthesized and its structure was confirmed by IR, MS, 1H NMR, and elemental analysis. The single crystal structure of the title compound was determined by X-ray diffraction. The crystal belongs to Monoclinic, space group P2 (1), with a = 0.69281(11) nm, b = 0.76508(12), c = 1.5843(3) nm, = 90°, β = 90.941(3)°, γ = 90°, V = 0.8397(2) nm3, Z = 2, Dc = 1.477 g/cm3, μ = 0.236 mm-1, F(000) = 392, R = 0.0297, and wR = 0.0664.  相似文献   

15.
The title compound N-(7-chloro-5-ethoxy-2H-[1,2,4]thiadiazolo[2,3-a]pyrimidin- 2-ylidene)- 2-(2,4-dichlorophenoxy)propanamide 3 has been synthesized through using bromine as cyclic reagent in 63% isolated yield. Suitable single crystals for X-ray diffraction were obtained by recrystallization from the mixture solvents at room temperature. Crystallographic data of 3: C16H13- Cl3O3S, Mr = 447.71, triclinic, space group P, a = 8.7461(8), b = 9.9560(10), c = 11.8572(11) , α = 94.341(2), β = 94.683(2), γ = 112.929(2)o, Z = 2, V = 941.21(15) 3, Dc = 1.580 g/cm3, F(000) = 456, R = 0.0794, wR = 0.2056 and μ(MoKα) = 0.623 mm-1. The title compound 3 was found to be effective in herbicidal activity.  相似文献   

16.
The title molecule, 3-(4-(dimethylamino)benzylidene)-l,5-dioxaspiro[5.5] unde- cane-2,4-dione (I), was synthesized and characterized by elemental analysis, IR, UV-vis spectra and X-ray diffraction analysis. The compound belongs to the triclinic system, space group Pi with a = 6.3640(6), b = 7.7404(8), c = 16.2890(18) A, α = 86.860(2), β = 85.837(2), γ = 79.6720(10)°, V = 786.60(14) A3, D, = 1.331 g/cm3, and F(000) = 336. Geometrical structure of the title compound was optimized by density functional theory (DFT) using B3LYP method with 6-31G** as the basis set. The vibrational frequencies were calculated by the DFT method and the results are consistent with the observed frequencies. The electronic absorption spectra were studied with the time- dependent density functional theory (TD-DFT), showing the calculation results in good agreement with the corresponding experimental data.  相似文献   

17.
18.
宋新建  王胜  汪焱钢 《结构化学》2006,25(4):402-406
1 INTRODUCTION 1,3,4-Thiadiazole derivatives represent an interes- ting class of compounds possessing broad spectrum biological activities[1~4]. Aroyl ureas are known to exhibit diverse biological effects, such as insecticidal, fungicidal, herbicidal and plant growth regulating activities[5~8]. Therefore, it is worthwhile to investi- gate the compounds incorporating both 1,3,4-thiadia- zole nucleus and aroyl urea group. In the previous paper[9], a series of aroyl ureas containing 1,3,4-t…  相似文献   

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