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新型3-取代-6-芳偶氮香豆素化合物的合成及结构表征   总被引:8,自引:0,他引:8  
合成了一系列新型偶氮香豆素化合物,通过^1H NMR,IR,MS和元素分析对其结 构进行了确认,同时用X射线单晶衍射测定了化合物2a的晶体结构,其特殊的双功 能分子键连,偶氮基的顺反异构和苯环与香豆素环平面间的扭转平角,使之可能成 为有效的分子器件材料。  相似文献   

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标题化合物C24H29NO4?1/2C2H5OH稨2O)由香兰素、5,5-二甲基-1,3-环己二酮、醋酸铵在微波辐射下干反应并经95%乙醇重结晶而得C24H29NO4穀2(C2H5OH稨2O)晶体。结构通过单晶X-射线衍射法确定,其晶体属单斜晶系,空间群P21/n, a = 9.810(2), b = 14.516(3), c = 17.008(3) ? b = 101.03(2), V = 2377.2(8) ?, Z = 4, Mr = 427.52, Dc = 1.195 g/cm3 , m(MoKa) = 0.082 mm-1, F(000) = 920。晶体结构用直接法解出,经全矩阵最小二乘法对原子参数进行修正,最终的偏离因子为R = 0.0406, wR = 0.0892。X-射线衍射分析结果表明,吡啶环和与之稠合的2个六员环均为信封式构象。  相似文献   

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(3Z,9Z,6S,7R)-6,7-epoxy-3,9-octadecadiene (1) and (3Z,9Z,6R,7S)-6,7-epoxy-3,9-octadecadiene (2) have been stereoselectively synthesized in eight steps from 2-pentyn-1-ol with an overall yield of 8%. The key steps involved the Sharpless asymmetric dihydroxylation of (2E)-oct-2-en-5-yn-1-ol (6). The new synthetic method is suitable for multigram-scale preparation of 1 and 2 and might be used for producing sufficient quantities of the sex pheromone components for management of the pest of tea plantations.  相似文献   

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邻硝基苯基荧光酮化学发光性能和机理研究   总被引:7,自引:1,他引:7  
谢增鸿 《分析化学》1998,26(6):684-688
研究了在碱性介质中金属离子催化邻硝基苯基荧光酮(o-NPF)-H2O2体系的化学发光行为。结果表明,在研究的20多种金属离子中,只有Co2+离子对o-NPF-H2O2体系有较强的催化发光作用,Co2+的浓度与发光强度在2.5×10-9~3.0×10-6g/mL范围内呈良好的线性关系。通过对化学发光光谱、荧光光谱的研究以及用Huckel分子轨道法(HMO)计算了o-NPF的π电子分布和键级,提出了o-NPF可能的化学发光机理.  相似文献   

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The anhydride and dimethyl ester of 4, 5-(1-benzyl-1, 2, 3-triazoline)-3, 6-endohexahydrophthalic acid, having a triazoline ring with an exo-cis configuration, are synthesized by reaction of benzyl azide with the furan-maleic anhydride adduct. Opening of the triazoline ring under the action of hydrochloric and acetic acids takes place with the separation of nitrogen and formation of the chloro and acetoxy derivatives, respectively, unaccompanied by a Wagner-Meerwein type of rearrangement.Part XXIV, see [1].  相似文献   

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标题化合物C23H25对O3Cl是由邻氯苯甲醛与5,5-二甲基1,3-环己二酮在N,N-二甲基甲酸腹中反应而得。结构通过单晶X-射线衍射法确定,其晶体属于单科晶系,空间群=1632。晶体结构用直接法解出,使用全矩阵最小二乘法对原子参数进行修正,最后的偏离因子为R=0.054,Rw一0.063。在晶体结构中,吡喃环与苯环之间的两面角为92.43°。  相似文献   

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Preparation of new carbazole-containing polymer, poly[9-hexadecyl-3-phenyl-6-(4-vinylphenyl)-9H-carbazole], is reported. The optical properties of the product have been studied in comparison with those of the starting compounds. Electrochemical properties of the polymer solution and its thin film have been investigated. The polymer film images were obtained by atomic force and scanning tunneling microscopy. Thermogravimetric analysis has shown high thermal stability of the obtained polymer.  相似文献   

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[reaction: see text] (-)-(6S,7S,8S,9R,10S,2'S)-Membrenone-A and (-)-(6S,7S,8S,9R,10S)-membrenone-B were prepared in 11 steps (3% and 2.4% overall yield, respectively). Key steps included a tin(II)-mediated aldol followed by a syn selective reduction, giving the C7-C9 stereocenters, a second chain extending aldol coupling, and a p-TsOH-promoted cyclization/dehydration giving the common gamma-dihydropyrone precursor. We have thus established that synthetic (-)-(6S,7S,8S,9R,10S,2'S)-membrenone-A, (-)-(6S,7S,8S,9R,10S)-membrenone-B, and (-)-(6S,7S,8S,9R,10S)-membrenone-C are the enantiomers of the natural products.  相似文献   

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1INTRoDUCTIONPhenylfluoroneisanimportanttypeofreagentinanalytica1chemistry"~'>.Themoleculesofthisreagenthavearigidplanarstructuret5'6i,sotheenergyofmolecularorbitsofthereagentscanbecalculatedbyHuckelmolecularorbitalmethod(HMO).WehadtriedtoassigndissociationconstantsforsomesuchreagentsbyacombinedspectrophotometricandHMOmethodt7'8i.Them.thodissimpleandtheresultsaresatisfactory.Inthispaper,apossiblemechanismforcatalyticchemiluminescencere-actionofCl-PFisproposedonthebasisofstudyingchemil…  相似文献   

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Tsang CW  Yang Q  Sze ET  Mak TC  Chan DT  Xie Z 《Inorganic chemistry》2000,39(16):3582-3589
The highly chlorinated, brominated, and iodinated carborane anions 1-R-CB9X9- (R = H, NH2; X = Cl, Br, I) were prepared in high yields by treatment of [Me3NH][1-R-CB9H9] with excess ICl, Br2/triflic acid, and I2/triflic acid, respectively, in sealed tubes at 180-240 degrees C. With the aid of a Pd catalyst, B-I bonds could be converted into the B-Me bonds by treatment with excess MeMgBr, which led to the preparation of the permethylated species 1-H-CB9Me9- in good yield. These new anions were fully characterized by 1H, 13C, and 11B NMR, IR, and negative-ion MALDI MS spectroscopy. Some were further characterized by single-crystal X-ray analyses. The weakly coordinating nature of these new anions was probed by 29Si chemical shifts.  相似文献   

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1,2-Digermacyclobut-3-enes were prepared by the treatment of Z-α,β-bis(chlorodialkylgermyl)ethenes with Na metal in boiling toluene and their structures were fully established by spectroscopic methods coupled with X-ray crystallography. In the presence of an appropriate catalyst, 1,2-digermacyclobut-3-enes reacted smoothly with alkynes to give the corresponding insertion products, 1,4-digermacyclohexa-2,5-dienes in moderate to good yields. Conventional complexes, such as [Pd(PPh3)4] and [Pt(PPh3)4], serve as efficient catalysts. The mechanism of the insertion reaction of alkynes into the germanium-germanium bond of 1,2-digermacyclobut-3-enes is discussed in terms of a key intermediate, a 1,4-digerma-2-buten-1,4-diylpalladium.  相似文献   

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The X-ray structures of the compounds 4 and 2 have been determined by direct methods and refined by least squares techniques. Crystals of C22H27NO5 and C27H27NO5 are triclinic, space groups with lattice parameters a = 13.652 (5) Å, b = 10.926 (3) Å, c = 7.755 (2) Å, a = 111.554 (4) Å, β = 85.541 (3) Å, γ = 104.813 (4) Å, and a = 15.394 (4) Å, b = 9.674 (3) Å, c = 8.522 (3) Å, a = 111.04 (4) Å, ß = 93.65 (4) Å, γ = 95.01 (4) Å, respectively.  相似文献   

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Summary 4a,6-Bis-(N-methylanilino)-7-hydroxy-2,3,8-trimethyl-4a,9a-dihydro-xanthene-dione (4) was obtained by thermolysis of 6-(N-methylanilino)-7a-methyl-3a,7a-dihydroindazol-4,7-dione (1) The structure was determined on basis of 1D- and 2D-NMR techniques.Herrn Prof. Dr. G. Zigeuner zum 70. Geburtstag gewidmet  相似文献   

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S. Hirano  H. Hara  T. Hiyama  S. Fujita  H. Nozaki 《Tetrahedron》1975,31(18):2219-2227
A new preparative sequence from 2,3-polymethylene-2-cyclopentenone 5 to 2,6-polymethylenebromobenzenes 3 (n = 6, 7, 10) and 2,6-polymethylenephenyllithiums 6 has been found. The reaction of 6 with various electrophiles produces a number of new compounds to disclose the unique reactivity of the aryl C-Li moiety surrounded by the polymethylene chain. Photolysis of 3a and 3b provides transannular products 8, 10 and 11, all arising from the proximity between the aromatic bromine and the aliphatic hydrogen intraannularly opposed to be removed as HBr. Spectrometric study gives quantitative data of the dependence of the molecular geometry upon the chain length and the aromatic substituents. The energy barriers ΔGc of the conformational flipping are 17·4 kcal/mol (Tc 76·5°) for [6]metacyclophane (7a), 11·5 kcal/mol (Tc ?28°) for [7]metacyclophane (7b), ·8 kcal/mol for [10]metacyclophane (7c). The lower-energy process of the aliphatic chain in [6]metacyclophane derivatives is the pseudorotation with substituent-dependent barrier ΔGc 11·1 kcal/mol (Tc ?31·5°) for 7a, 12·4 kcal/mol (Tc ?4·5°) for 3a and 12·7 kcal/mol (Tc 1·0°) for 12a. The rather large rotational barrier is attributed to the compressed structure of each system. The benzene ring distortion of the cyclophanes is deduced from the bathochromic shift of the B-band and the diamagnetic shift of the benzene proton signals in the PMR.  相似文献   

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《印度化学会志》2021,98(3):100040
To isolate the metal-rich metallaboranes of group 6-9, we have performed the reaction of various reaction intermediates, generally synthesized from the low-temperature reactions of [Cp1WCl4] (Cp1 ​= ​η5-C5Me5), [(Cp1RhCl2)2], or [(Cp1RuCl2)2] and [LiBH4 THF] with different transition metal carbonyl compounds. For example, the thermolytic reaction of [Fe2(CO)9] with an in situ generated intermediate, produced from the reaction of [Cp1WCl4] and [LiBH4THF] afforded a trigonal bipyramidal cluster, [(μ3-BH)2H2{Cp1W(CO)2}{Cp1W(CO)}{Fe(CO)3}], 1 which contains a triply-bridging bis-{hydrido(borylene)} ligand. Similarly, the reaction of [Co2(CO)8] with nido-[(RhCp1)2(B3H7)] I at room temperature, yielded an octahedral cluster, [(Cp1Rh)2B2H2Co2(CO)5(μ3-CO)], 2. In this reaction, nido-I having (n+2) skeletal electron pairs (SEP) goes on for the formation of a closo-rhodaborane with (n+1) SEP. In addition, we have isolated a trinuclear bis(μ3-oxo) metalla cluster [(Cp1Ru)3(μ3-OBF3)2(μ-H)], 3. Compound 3 can be considered as cluster having trigonal bipyramidal geometry with exo-BF3 fragment. All these clusters were characterized by IR, mass spectrometry, NMR, and single-crystal X-ray crystallographic analysis.  相似文献   

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用化学动力学控制的方法在化合物3的5-C上C=O与6-C发生烯醇化生成锂盐,然后可在6-C位分别引入甲基、烯丙基、苄基、溴以及羟基取代基。产物6、7、8、9a和11经鉴定,除9α外其他都是α和β构型的混合物,其中以α-构型取代物为主。  相似文献   

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