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1.
以间羟基苯甲酸为起始原料通过7步反应合成了15个新颖的N′-叔丁基-N′-取代苯甲酰基-N-(苯并二氢吡喃-5-甲酰基)肼类化合物. 中间体3-炔丙氧基苯甲酸甲酯在N,N-二乙基苯胺中发生克莱森重排后得到主要产物苯并吡喃-5-甲酸甲酯和副产物苯并吡喃-7-甲酸甲酯. 通过氢谱、元素分析或高分辨质谱确定了这些化合物的结构, 化合物1a的X射线单晶衍射分析发现苯并二氢吡喃的吡喃环与苯环不共平面, 其中的C(1)和C(2)分别位于相应苯环平面的两侧.  相似文献   

2.
异苯并二氢吡喃-4-酮(1),至今在天然化合物中尚未发现。Normant 等人进行早期的合成工作之后,另一些科学家由1及其衍生物合成了一些有用的有机化合物,如盾母醇(Peltogynol)类似物、黄过氯酸盐(Flavylium Perchlorate)、雌二醇杂环类似物、雌酮杂环类似物和苯并吡喃糖苷的氨基衍生物等。这  相似文献   

3.
陈晓东  叶姣  胡艾希 《有机化学》2012,32(3):520-525
鱼藤酮与氧硫叶立德反应得到关键中间体(5,6-二甲氧基-1,1a,2,7b-四氢环丙并[c]苯并吡喃-7b-基)[(R)-4-羟基-2-(丙烯-2-基)-2,3-二氢苯并呋喃-5-基]甲酮(2),2再通过醚化、肟化、贝克曼重排得到5,6-二甲氧基-N-[(R)-4-甲氧基-2-(丙烯-2-基)-2,3-二氢苯并呋喃-5-基]-1,1a,2,7b-四氢环丙并[c]苯并吡喃-7b-基甲酰胺(5),化合物的结构经1H NMR,MS和元素分析确认,采用单晶X射线衍射法确定化合物5的晶体结构.化合物5属于三斜晶系,P1空间群,晶胞参数:a=0.95772(5)nm,b=1.06591(6)nm,c=1.30112(7)nm,α=111.8460(10)°,β=109.8870(10)°,γ=93.0870°,V=1.13429(11)nm3,Z=2,Dc=1.281 g/cm3,μ(Mo Kα)=0.092 mm-1,F(000)=464.  相似文献   

4.
为开发新型环境友好杀菌剂,选择了黄烷酮类植物抗毒素为先导,利用生物等排取代原理对其结构进行修饰,设计合成了23个未见文献报道的2-杂环芳基苯并二氢吡喃-4-酮类化合物,并系统测定了所有化合物对水稻稻瘟病抑制活性的IC~5~0值。在此基础上,采用CoMFA方法对它们进行了三维定量结构活性关系研究,系统考查了网格结构、探针以及场类型对CoMFA结果的影响。研究结果表明,苯并二氢吡喃-4-酮苯环5,6,7位上应该引入一些体积较小且具有强供电子能力的取代基有利于提高化合物的杀菌活性。CoMFA分析对7位氧原子和19位氧原子的电性要求与前文采用Hansch-Fujita方法的分析结果是相一致的。  相似文献   

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3-疏基香豆素及其衍生物的研究   总被引:1,自引:0,他引:1  
研究了3-疏基香豆素(8)、3,3'-二硫代双香豆素的合成及8与一系列Michael受体的反应.按受体结构不同,除都能发生分子间的加成反应外,有些还可进一步发生第二次分子内的加成反应,关环后得到一系列四氢噻吩并[2,3-C][1]苯并吡喃-4(H)-酮的衍生物.对这些化合物的立体化学及结构进行了鉴定.8分别和烯丙基溴、肉桂基溴缩合,前者在N,N-二甲苯胺内发生正常的Claisen重排,得到1,2-二氢-2-甲基噻吩并[2,3-C][1]苯并吡喃-4-(H)-酮及1,2,3,5-四氢硫代吡喃并[2,3-C][1]苯并吡喃-5-酮,但后者的反应产物是3-(ρ-N,N-二甲氨基)苄硫基香豆素.  相似文献   

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设计合成了三类含1,2,3-三氮唑结构的1,5-苯并硫氮杂?化合物3-(1H-1,2,3-三氮唑)-4-芳基-2,5-二氢-1,5-苯并硫氮杂?(5a~5f)、3-(2H-1,2,3-三氮唑)-4-芳基-2,3-二氢-1,5-苯并硫氮杂?(6a~6f)和3-(1H-1,2,3-三氮唑)-4-芳基-2,3,4,5-四氢-1,5-苯并硫氮杂?(7a~7f).研究了中间体及目标产物的合成条件,分离出其中两个副产物并进行了结构确定.目标产物的抑真菌活性测试表明,化合物5a~5f对真菌具有良好的抑制作用,对新生隐球菌的抑制效果尤为突出.初步抑真菌构效关系研究表明, 1H-1,2,3-三氮唑环和C=C双键是化合物5a~5f抑真菌活性的关键官能团.  相似文献   

7.
通过4-羟基香豆素与苯甲醛、甲醛和戊醛缩合产生的quinone methide与烯醇硅醚的Diels-Alder反应, 以较高产率合成了一系列含有硅氧基的3,4-二氢-2H,5H-吡喃并[3,2-c][1]苯并吡喃-5-酮衍生物. 用X射线单晶衍射确定了其中5个化合物的空间构型. 利用密度泛函(DFT)方法计算反应物之间的前线分子轨道相互作用, 对反应的区域选择性进行了研究, 计算结果与实验值相符.  相似文献   

8.
本文报道了3-巯基香豆素(8)、3,3′-二硫代双香豆素(9)的合成及8与一系列Michael受体的反应。按受体结构不同,除都能发生分子间的加成反应外,有些还可进一步发生第二次分子内的加成反应,关环后得到一系列四氢噻吩并[2,3-C][1]苯并吡喃-4(H)-酮的衍生物。对这些化合物的立体化学及结构进行了鉴定。8分别和烯丙基溴、肉桂基溴缩合,前者在N,N-二甲苯胺内发生正常的Claisen重排,得到1,2-二氢-2-甲基噻吩并[2,3-C][1]苯并吡喃-4(H)-酮(27)及1,2,3,5-四氢硫代吡喃并[2,3-C][1]苯并吡喃-5-酮(28),但后者的反应产物是3-(p-N,N-二甲氨基)苄硫基香豆素(32)。  相似文献   

9.
设计合成了三类含1,2,3-三氮唑结构的1,5-苯并硫氮杂[艹卓]化合物3-(1H-1,2,3-三氮唑)-4-芳基-2,5-二氢-1,5-苯并硫氮杂[艹卓](5a^5f)、3-(2H-1,2,3-三氮唑)-4-芳基-2,3-二氢-1,5-苯并硫氮杂[艹卓](6a^6f)和3-(1H-1,2,3-三氮唑)-4-芳基-2,3,4,5-四氢-1,5-苯并硫氮杂[艹卓](7a^7f).研究了中间体及目标产物的合成条件,分离出其中两个副产物并进行了结构确定.目标产物的抑真菌活性测试表明,化合物5a^5f对真菌具有良好的抑制作用,对新生隐球菌的抑制效果尤为突出.初步抑真菌构效关系研究表明, 1H-1,2,3-三氮唑环和C=C双键是化合物5a^5f抑真菌活性的关键官能团.  相似文献   

10.
李诤  王全瑞  陶凤岗 《有机化学》2004,24(8):893-897
取代苯并二氢吡喃-4-酮(1)的芳腙在冰醋酸中与KNCO发生[3 2]环加成反应,加成产物经KMnO4氧化开环得偕偶氮异氰酸酯(3).3在HBF4的催化下发生环化-重排反应,合成得到一系列新型6-7-5三环系1,2,4-三唑并[3,2-d][1,5]苯并氧氮杂(艹卓)2-酮(5a~5g).由X单晶衍射测定了化合物5a的晶体结构.  相似文献   

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A low barrier in the reaction pathway between the double Rydberg isomer of OH(3) (-) and a hydride-water complex indicates that the former species is more difficult to isolate and characterize through anion photoelectron spectroscopy than the well known double Rydberg anion (DRA), tetrahedral NH(4) (-). Electron propagator calculations of vertical electron detachment energies (VEDEs) and isosurface plots of the electron localization function disclose that the transition state's electronic structure more closely resembles that of the DRA than that of the hydride-water complex. Possible stabilization of the OH(3) (-) DRA through hydrogen bonding or ion-dipole interactions is examined through calculations on O(2)H(5) (-) species. Three O(2)H(5) (-) minima with H(-)(H(2)O)(2), hydrogen-bridged, and DRA-molecule structures resemble previously discovered N(2)H(7) (-) species and have well separated VEDEs that may be observable in anion photoelectron spectra.  相似文献   

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17.
Summary Dichlorobis(methylsalicylato)titanium(IV) reacts with potassium or amine salts of dialkyl or diaryl dithiocarbamates in 11 and 12 molar ratios in anhydrous benzene (room temperature) or in boiling CH2Cl2 to yield mixed ligand complexes: (AcOC6H4O)2 Ti(S2CNR2)Cl (1) and (AcOC6H4O)2 Ti(S2CNR2)2 (2), R=Et, n-Pr, n-Bu, cyclo-C4H8 and cyclo-C5H10. These compounds are moisture sensitive and highly soluble in polar solvents. Molecular weight measurement in conjunction with i.r.,1H and13C n.m.r. spectral studies suggest coordination number 7 and 8 around titanium(IV) in (1) and (2) respectively.  相似文献   

18.
Huang FQ  Ibers JA 《Inorganic chemistry》2001,40(10):2346-2351
The alkali metal/group 4 metal/polychalcogenides Cs(4)Ti(3)Se(13), Rb(4)Ti(3)S(14), Cs(4)Ti(3)S(14), Rb(4)Hf(3)S(14), Rb(4)Zr(3)Se(14), Cs(4)Zr(3)Se(14), and Cs(4)Hf(3)Se(14) have been synthesized by means of the reactive flux method at 823 or 873 K. Cs(4)Ti(3)Se(13) crystallizes in a new structure type in space group C(2)(2)-P2(1) with eight formula units in a monoclinic cell at T = 153 K of dimensions a = 10.2524(6) A, b = 32.468(2) A, c = 14.6747(8) A, beta = 100.008(1) degrees. Cs(4)Ti(3)Se(13) is composed of four independent one-dimensional [Ti(3)Se(13)(4-)] chains separated by Cs(+) cations. These chains adopt hexagonal closest packing along the [100] direction. The [Ti(3)Se(13)(4-)] chains are built from the face- and edge-sharing of pentagonal pyramids and pentagonal bipyramids. Formal oxidation states cannot be assigned in Cs(4)Ti(3)Se(13). The compounds Rb(4)Ti(3)S(14), Cs(4)Ti(3)S(14), Rb(4)Hf(3)S(14), Rb(4)Zr(3)Se(14), Cs(4)Zr(3)Se(14), and Cs(4)Hf(3)Se(14) crystallize in the K(4)Ti(3)S(14) structure type with four formula units in space group C(2)(h)()(6)-C2/c of the monoclinic system at T = 153 K in cells of dimensions a = 21.085(1) A, b = 8.1169(5) A, c = 13.1992(8) A, beta = 112.835(1) degrees for Rb(4)Ti(3)S(14);a = 21.329(3) A, b = 8.415(1) A, c = 13.678(2) A, beta = 113.801(2) degrees for Cs(4)Ti(3)S(14); a = 21.643(2) A, b = 8.1848(8) A, c = 13.331(1) A, beta = 111.762(2) degrees for Rb(4)Hf(3)S(14); a = 22.605(7) A, b = 8.552(3) A, c = 13.880(4) A, beta = 110.919(9) degrees for Rb(4)Zr(3)Se(14); a = 22.826(5) A, b = 8.841(2) A, c = 14.278(3) A, beta = 111.456(4) degrees for Cs(4)Zr(3)Se(14); and a = 22.758(5) A, b = 8.844(2) A, c = 14.276(3) A, beta = 111.88(3) degrees for Cs(4)Hf(3)Se(14). These A(4)M(3)Q(14) compounds (A = alkali metal; M = group 4 metal; Q = chalcogen) contain hexagonally closest-packed [M(3)Q(14)(4-)] chains that run in the [101] direction and are separated by A(+) cations. Each [M(3)Q(14)(4-)] chain is built from a [M(3)Q(14)] unit that consists of two MQ(7) pentagonal bipyramids or one distorted MQ(8) bicapped octahedron bonded together by edge- or face-sharing. Each [M(3)Q(14)] unit contains six Q(2)(2-) dimers, with Q-Q distances in the normal single-bond range 2.0616(9)-2.095(2) A for S-S and 2.367(1)-2.391(2) A for Se-Se. The A(4)M(3)Q(14) compounds can be formulated as (A(+))(4)(M(4+))(3)(Q(2)(2-))(6)(Q(2-))(2).  相似文献   

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Pure, highly explosive CF(3)C(O)OOC(O)CF(3) is prepared for the first time by low-temperature reaction between CF(3)C(O)Cl and Na(2)O(2). At room temperature CF(3)C(O)OOC(O)CF(3) is stable for days in the liquid or gaseous state. The melting point is -37.5 degrees C, and the boiling point is extrapolated to 44 degrees C from the vapor pressure curve log p = -1875/T + 8.92 (p/mbar, T/K). Above room temperature the first-order unimolecular decay into C(2)F(6) + CO(2) occurs with an activation energy of 129 kJ mol(-1). CF(3)C(O)OOC(O)CF(3) is a clean source for CF(3) radicals as demonstrated by matrix-isolation experiments. The pure compound is characterized by NMR, vibrational, and UV spectroscopy. The geometric structure is determined by gas electron diffraction and quantum chemical calculations (HF, B3PW91, B3LYP, and MP2 with 6-31G basis sets). The molecule possesses syn-syn conformation (both C=O bonds synperiplanar to the O-O bond) with O-O = 1.426(10) A and dihedral angle phi(C-O-O-C) = 86.5(32) degrees. The density functional calculations reproduce the experimental structure very well.  相似文献   

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