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三甲基苯乙酮肟;立体异构体;(Z)-2-(1H-咪唑-1-基)-1-(2;3;4-三甲氧基)苯乙酮肟酯的设计与合成  相似文献   

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1 INTRODUCTION The vinyl sulfones are versatile intermediates in organic chemistry and have been extensively stu- died[1]. The available methodology for vinyl sulfone synthesis mainly consists of Horner-Emmons reac- tions of carbonyl compounds with sulf…  相似文献   

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The synthesis of (Z)-4-hydroxytamoxifen and (Z)-2-[4-[1-(p-hydroxyphenyl)-2-phenyl]-1-butenyl]phenoxyacetic acid was accomplished using a McMurry reaction as the key step. The perfluorotolyl derivatives of the McMurry products enabled the separation of the minor undesirable geometrical isomer. The methodology proceeds without E,Z isomerization, employs a very mild final debenzylation step compatible with a large array of functional groups, and can be applied to the generation of a variety of 4-hydroxytamoxifen analogues.  相似文献   

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A highly stereoselective method to prepare both (E)- and (Z)-alpha-fluorostilbenes is described. 1-Bromo-1-fluoroalkenes (E/Z approximately 1:1), a readily available starting material, isomerizes to high E/Z ratios by storage at -20 degrees C or by photolysis at 254 nm. Stille coupling between these high E/Z 1-bromo-1-fluoroalkenes and aryl stannanes gave (Z)-alpha-fluorostilbenes in high stereoselectivity. (Z)-1-Bromo-1-fluoroalkenes, which were kinetically separated from 1-bromo-1-fluoroalkenes (E/Z approximately 1:1), can participate in Suzuki coupling reactions to give (E)-alpha-fluorostilbenes stereoselectively.  相似文献   

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A simple method for the preparation of the title compounds via the reaction of dimethyl 2-ethenylcyclopropane-1,1-dicarboxylate with 6M ammonia in methanol is described.  相似文献   

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Summary.  Epoxidation of (Z)-3-arylidene-1-thioflavanones by sodium hypochlorite or alkaline hydrogen peroxide afforded diastereomeric mixtures of trans,cis- and trans,trans-epoxides. These were separated by silica gel column chromatography. Determination of the isomeric composition of the crude reaction products and structure elucidation of all new isolated epoxides were performed by 1H and 13C NMR spectroscopy. Received November 10, 2000. Accepted December 19, 2000  相似文献   

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通过1-苯基-2-对甲苯磺酰基乙炔、对氟苯基氯化锌及烯丙基溴的三组分串联反应,合成了(Z)-1-苯基-1-对氟苯基-2-对甲苯磺酰基-1,4-戊二烯(1),其结构经1H NMR, 13C NMR, IR, HR-MS和XRD表征.1为Z-构型,属单斜晶系,空间群P21/c, a=9.899 1(20)(A), b=9.621 9(20)(A), c=21.812 9(15)(A), β=95.575(10)°, V=2067.8(6)(A)3, Z=4, Dc=1.254 g·cm3, μ=0.181 mm-1, λ=0.710 73(A), F(000)=816, R=0.046 3, wR=0.134 1.共收集到3 684个独立衍射点,其中I>2σ(I)的可观察点为2 989.  相似文献   

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[reaction: see text] A novel type of cascade ring expansion process has been developed by the palladium-catalyzed reaction of (Z)-1-(1,3-butadienyl)cyclobutanols with aryl iodides. The reaction proceeds in a stereospecific manner to produce (Z)-2-(3-aryl-1-propenyl)cyclopentanones. It has also been found that regioselective alpha-arylation of alkenyl cyclopentanones proceeds to afford the alpha-arylated cyclopentanones.  相似文献   

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报道了标题化合物〔C14H18Br2OSn〕的合成及晶体结构。该晶体属于单斜晶系,空间点群为P21/c,晶胞参数a=11.711(2),b=9.114(2),c=16.864(3)A,β=102.94(1)°,V=1604.55(0)A3,Mr=480.78,Z=4,Dc=1.99g/cm3,u=65.20cm-1,F(000)=919,R=0.050,Rw=0.050.晶体结构由直接法解出。标题化合物分子中的锡原子被配体的2个碳、2个溴和1个氧原子配位,配位原子呈畸变的三角双锥构型,环已基为椅式构象,五员杂环为信封构象。  相似文献   

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有机锡化合物的抗癌活性与结构的关系是人们所关注的一个重要课题[1.2].自1989年以来,我们合成了几个系列的C-Sn直接相连并在分子中存在O→Sn内配位的有机锡化合物[3].经过抗癌活性实验,发现其中有很多种具有较高的抗癌活性.本文所报道的标题化合物分子有两种构型,迄今为止未见类似的报道.标题化合物的抗癌活性正在测试中.1实验部分1.且仪器1106型元素分析仪;锡含量用重量法分析;NicoletR。M/E四圆衍射仪.1.2标题化合物的合成(Z)-l{2-(二苯基演化锡基)乙烯基11一环己醇(I)按照文献["方法合成.产率80%,m.卜14…  相似文献   

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(E)- and (Z)-1-benzenesulfonyl-4-trimethylsilyl-2-butenes (E/Z=9), prepared from 4-trimethylsilyl-1-buten-3-ol, n-butyllithium and benzenesulfenyl chloride and oxidation of the intermediate (E)- and (Z)-1-benzenesulfinyl-4-trimethylsilyl-2-butenes with hydrogen peroxide, react with n-butyllithium and then primary halides to give 4-benzenesulfonyl-1-trimethylsilyl-2-alkenes which are rapidly 1,4-debenzenesulfonyltrimethylsilated to (E)-1,3-alkadienes by tetra-n-butylammonium fluoride at O°C.  相似文献   

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