首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 78 毫秒
1.
从(-)-(1S,2R,4S)-5,6-二亚甲基双环[2.2.1]庚-2-醇(I)和(-)-(1S,2S,4S)-5,6-二亚甲基双环[2.2.1]庚-2-醇(Ⅱ)出发,合成了它们的醚类和取代苯甲酸酯类光学纯的衍生物。通过[α]D测定和构型分析,发现它们是含有3个手性碳(C1,C2和C4)的桥环化合物,其旋光性与构型的关系均符合可极化度多级圆球不对称性模型。  相似文献   

2.
蒋旭东  俞雄  袁哲东 《合成化学》2013,21(3):302-305
以反式-4-羟基-L-脯氨酸为原料,经氮烷基化、酯化、磺酰化、硫代乙酸钾反应构型转换、水解酯基、缩合和成盐反应合成了5个新型的(2S,4S)-5-烷基-2-硫杂-5-氮杂双环[2.2.1]庚-3-酮衍生物,其结构经1H NMR和MS表征。  相似文献   

3.
报道了标题化合物合成和晶体结构。X-射线结构分析表明,该化合物的分子式为C39H58BrO10P,Mr = 797.74,晶体属于单斜晶系,空间群为P21,晶胞参数a = 12.858(3), b = 25.130(5), c = 14.125(3) ? = 105.15(3), V = 4405(2) ?, Z = 4, Dc = 1.203 g/cm3, ?= 1.019 mm-1, F(000) = 1688,R = 0.0726, wR = 0.1201,共收集到9691个独立衍射点,其中可观测点5638个(I≥2s(I))。每个分子中有6个环,13个手性中心,2个五员环呈信封式构象,并分别与三员环组合成[2.4]螺环和[3.1.0]桥环化合物,4个新生成的手性中心的绝对构型为C(6)(S), C(7)(S), C(3)(R), C(2)(R),新引入的磷酸酯官能团C(9)为S构型。  相似文献   

4.
1,6-亚甲基桥[10]轮烯-4-溴-3-羧酸乙酯经LiAlH4还原后再在冰水浴下与PBr3反应制得3-溴甲基-4-溴-1,6-亚甲基桥[10]轮烯(3);3与PPh3在苯中回流,然后与对甲氧基苯甲醛进行Wittig反应,再经分子内异构化制得3-(p-甲氧基苯乙烯基)-4-溴-1,6-亚甲基桥[10]轮烯(trans-5);trans-5在钯盐催化下完成分子间耦合合成了基于1,6-亚甲基桥[10]轮烯的多环化合物,其结构经NMR,IR和MS表征.  相似文献   

5.
合成的标题化合物用X射线衍射方法确定其分子的绝对构型,晶体空间群为P_(2_1 2_1 2_1),晶胞参数:a=0.8365(3)、b=0.8625(3)、c=2.3513(2)nm,Z=4.结构分析表明,分子骨架中存在3个环结构,即含磷、氮原子的船式七元环、椅式六元环以及由碳原子组成的信封式五元环。P—S键为e键,P—O键为a键。  相似文献   

6.
标题化合物是由5-(R)-(l-孟氧基)-2(5H)-呋喃酮与3,4-亚甲二氧基苯甲醛肟在次氯酸钙作为氧化剂的条件下,进行的区域选择性原位1,3-偶极环加成反应得到。结构通过单晶X-射线衍射法确定, C22H27NO6其晶体属正交晶系, 空间群为P212121, Mr = 401.45, a = 6.2600(3), b = 10.7300(11), c = 31.2160(25) , V = 2096.8(3) 3, Z = 4, Dc = 1.272 g/cm3, μ = 0.09 mm-1, F(000) = 856。最终的可靠因子为R f = 0.073, wR = 0.186。在分子结构中,平面1(异噁唑啉环)与平面2(呋喃酮环)之间的二面角为67.4°, 孟氧基中的环己烷环为椅式构象,呋喃酮并异噁唑啉环上的3个手性中心的构型为SC3a, RC6, RC6a。  相似文献   

7.
合成了R,S一三[N-(邻-氧α-萘亚甲基)-α-苯乙胺]合钴。x射线单晶衍射衍射测定了晶体结构及分子的绝对构型。晶体属正交晶系,D_2~4-P2_12_12_1空间群,晶胞参数:α=12.587(3),b=14.166(3),c=25.652(14)(?),v=4574.2(?)~3,z=4。用重原子法及差值Fourier合成解出结构,最后的R值为0.074。利用Co~( )对CuKa反常散射测定了分子的绝对构型。Co~( )为六配位,d~2sp~3杂化近正八面体构型。  相似文献   

8.
绝大部份商品环氧树脂皆由双酚与环氧氯丙烷缩合而得,其最明显的缺点是粘度较大和耐温性能较差。近年来,在国外有不少报告,某些环氧化多烯可以避免这些缺点。但关于含双环[2.2.1]庚烷环的环氧化物则很少研究。本文报告有关这类环氧化物的合成及其固化的研究结果。作者按下列方式合成含双环[2.2.1]庚烷环的双环氧化物:  相似文献   

9.
穆华荣  姚勇  颜朝国 《应用化学》2015,32(12):1416-1422
为深入开展杯芳烃为骨架的超分子拓扑结构的组装和性能,开展了间苯二酚杯芳烃八取代吡啶酰胺的合成和分子结构的研究。 以四丙基、四己基和四庚基间苯二酚杯芳烃为原料,使用α-氯乙酸甲酯实现O-烃基化,后者在无溶剂条件下与2-氨甲基吡啶反应实现酰胺化,制备了烷基间苯二酚杯芳烃八[N-(2-吡啶甲基)乙酰胺]衍生物。 用X衍射方法测定了四丙基间苯二酚杯芳烃八乙酸甲酯、四丙基以及四己基间苯二酚杯芳烃八[N-(2-吡啶甲基)乙酰胺]的单晶分子结构。 在晶体中,间苯二酚杯芳烃都以全顺式构型存在,在成环的四个间苯二酚单元中,1,3-位的两个间苯二酚单元处于近直立构象,2,4-位的另两个间苯二酚单元处于近平伏构象,而4个烷基皆处于分子的下缘,8个乙酰胺支链伸向分子的外围。  相似文献   

10.
A series of new optically active [2-(1-hydroxyalkyl)pyrrolidino]methylferrocenes were conveniently prepared from commercially available L-proline and ferrocenecarboxylic acid. The crystal structure of key intermediate was obtained. They were then applied to catalyze enantioselective addition of diethylzinc to arylaldehydes with enantioselectivity up to 99%. The effects of the ligand structures on the enantioselectivity were also studied.  相似文献   

11.
1-甲基 - 7-氧杂双环 [2 .2 .1 ]庚烷 - 2 -酮 ( 1 )是萜类天然产物全合成中的重要中间体 ,能被广泛地应用于多种桉烷 ( Eudesmane)、沉香呋喃 ( Agarofuran)和降胡萝卜素 ( Norcarotenoids)等倍半萜天然产物的全合成[1,2 ] .我们以对映体纯化合物 1为原料 ,实现这类天然产物的不对称全合成 [3~ 6 ] .消旋的化合物 (± ) - 1可以 2 -甲基呋喃和 2 -氯丙烯腈为原料 ,经 3步反应得到 [2 ] .但对映体纯化合物 1的制备尚未见报道 .本文用化学拆分方法 ,成功地制备了对映体纯的 ( + ) - 1和 ( - ) - 1 ,并确定了其绝对构型 .1 结果与讨论为减…  相似文献   

12.
A novel gold‐catalyzed cycloisomerization of 1,6‐diynes was achieved, providing an atom‐economic approach to a diverse set of bicyclo[2.2.1]hept‐5‐en‐2‐ones in moderate to good yields. With unsymmetrical starting materials with two different internal alkynyl substituents, to some extent, the regioselectivity could be controlled by both electronic and steric factors. This unprecedented reactivity pattern may inspire new and unconventional strategies for the preparation of bridged ring systems.  相似文献   

13.
用DFT方法研究了氮杂炔正离子[R-C≡N-CH3] 与二环[2,2,1]-2-庚烯的反应机理。所有几何构型用B3LYP/6-31G**基组进行优化,过渡态通过振动分析和内聚反应坐标进行了确认。并在相同基组上研究了当R为不同取代基时的反应变化规律。结果表明该反应为环加成反应,有两条反应途径,产物主要通过能量较低的过渡态TSa生成。当取代基为支链烷烃基团时,反应位垒较大;取代基为直链烷烃基团和苯环时,反应较易进行。  相似文献   

14.
Comparison of experimental and calculated chemical shifts of carbon atoms in13C NMR spectra of two isomeric dodecacyclo[14.9.1.14,13.17,10.02,15.03,14.05,12.06,11.017,25.018,24.019,21. 020,24]-octacos-8-enes, bicyclo[2.2.1]heptadiene tetramers, confirmed theirexo-trans-exo-trans-exo-endo-andexo-trans-exo-trans-exo-exo-configurations. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2545–2547, December, 1998.  相似文献   

15.
Metathesis of spirocyclo[2.2.1]hept-2-ene-7,1'-cyclopropane and its co-metathesis with norbornene and 5-decene on homogeneous and heterogeneous catalytic systems were carried out for the first time. The reactions were shown to proceed with retention of the spirosystem.Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 138–139, January, 1993.  相似文献   

16.
1 INTRODUCTION Low-valent titanium reagents have exceedinglyhigh abilities to promote reductive coupling of car-bonyl compounds and they are attracting increasinginterest in organic synthesis[1]. Many other func-tional groups can also be coupled[2~8]. Recently, wehave reported some intermolecular reductive cou-pling reactions[9~12] and some new intramolecular re-ductive coupling reactions[13~16] induced by low-va-lent titanium reagents. The spiro[4.4]nonane skeleton has been found inmany…  相似文献   

17.
[formula: see text] The syntheses of both exo and endo stereoisomers of 7-methyl-7-azabicyclo[2.2.1]heptan-2-ol were achieved in straightforward fashion. Alternatively, the intramolecular cyclization of syn-4-N-methylaminocyclohexane 1,2-epoxide was found to give exo-7-methyl-7-azabicyclo-[2.2.1]heptan-2-ol as the sole product. The stereochemistry of the exo isomer was unequivocally confirmed by X-ray crystallography.  相似文献   

18.
以Pictet-Spengler型反应为基础, 设计了一条简便的合成1,6-二取代-5,6-二氢吡咯并[1,2-f]蝶啶衍生物的方法. 以4,6-二氯-5-氨基嘧啶为起始原料, 经Clauson-Kaas反应、胺亲核取代两步反应合成了4-氨基-6-氯-5-(1H-吡咯-1-基)-嘧啶, 然后与醛或脂肪酮在对甲苯磺酸催化下, 发生亲电关环得到1-氯-5,6-二氢-6-取代吡咯并[1,2-f]蝶啶, 其1位氯原子具有较高的反应活性, 易于被胺类亲核试剂取代.  相似文献   

19.
A new monomer, 2-methylene-7-oxabicyclo[2.2.1]heptane ( IV ) was synthesized via four steps. Its structure was confirmed by IR, 1H-NMR, and 13C-NMR spectra as well as elementary analysis. Free radical polymerization and copolymerization of IV were investigated. No homopolymer was obtained due to the effect of allyl inhibition. When IV copolymerized with electron-donor monomers, such as vinyl acetate and stvrene, IV acted as inhibitor for the polymerization of vinyl acetate, but could not inhibit the polymerization of styrene. However, the copolymers of IV with electron-accepting monomers, such as methyl methacrylate, acrylonitrile, or maleic anhydride (MA) were obtained. The contents of IV in the copolymers increased as e values of electron-accepting monomers increased. Strictly alternating copolymer was obtained only in the case of MA and IV . The thermal properties of copolymers were investigated. © 1995 John Wiley & Sons, Inc.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号