首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 78 毫秒
1.
章慧 《大学化学》1996,11(2):49-52
结合对[Co(NH3)5Cl]^2)与[Co(NH3)6]^3+的颜色的比较,阐述配体场理论中有关电子组态、能级、轨道、配体场谱项及谱项间跃迁等基本概念及难点。即使不做严格的量子化学计算,从直观的物理模型、简单的分子轨道理论、群论方法及有关谱图中也能获得有用信息。  相似文献   

2.
合成了14种新的(Z)-[2-(三芳基锡基)乙烯基]环戊醇类有机锡化合物,通过元素分析,IR、^1H NMR 对所合成的化合物进行了表征,结果表明(Z)-[2-(三芳基锡基)乙烯基]环戊醇类有机锡化合物中乙烯式双键为顺式构型,分子内羟基与锡原子发生配位,形成五元螯合环。生物活性测定结果表明,二卤化物在抗癌,免疫及受体作用等方面具有优良的活性。  相似文献   

3.
姜世梅  梁映秋 《结构化学》1994,13(3):206-210
用四甲基环戊二烯基[C_5HMe_4]~-为配体合成了夹心化合物[C_5HMe_4]_2TiCl_2,通过核磁共振、质谱、红外光谱、拉曼光谱等多种谱学方法对该化合物进行了结构表征,实验结果表明[C_5HMe_4]_2TiCl_2中两个[C_5HMe_4]~-配体对称分布在Ti(Ⅳ)两侧,整个分子具有C_2v对称性,呈覆盖型结构。  相似文献   

4.
钯催化α-(6-甲氧基-2-萘基)乙醇的不对称羰基化反应   总被引:2,自引:0,他引:2  
不对称羰基化可产生多种手性分子,而这些手性分子是合成药物和农药等重要前体[1].光学活性的α-芳基丙酸类如S-布洛芬和萘普生是很重要的非麻醉性镇痛消炎药.以不对称氢甲酰化反应和氢羧基化反应制备光学活性的布洛芬和萘普生已有报道[2,3],但这些不对称羰...  相似文献   

5.
铕(Ⅲ)三元配合物荧光性质的研究   总被引:2,自引:0,他引:2  
利用Eu(Ⅲ)、Tb(Ⅲ)等稀土离子有机配合物发光性能作为蛋白质的荧光标记,对抗体或抗原进行微量分析是近年发展起来的免疫荧光分析的一种重要分析测试技术[1]。氟代β-二酮配合物不仅能有效提高配合物分子内能量传递,同时也减少有机配体和稀土离子非辐射跃迁能量散射,并与金属离子形成具有较强荧光的稀土配合物[2,3]。为了避免溶剂分子及水分子所引起荧光淬灭,中性配体也十分重要[4.5]。本文选用噻吩甲酰三氟丙酮(TTA)、苯甲酰三氟丙酮(BTA)、苯甲酰丙酮(BA)为配阴离子,以1,10-邻菲绕啉(Ph…  相似文献   

6.
用α-Keggin杂多阴离子XW12On-40与三芳基氢氧化锡Ar3SnOH反应,合成了四个三芳基锡杂多配合物{[Ar3Sn(CH3CH2OH)]+n[XW12O40]n-}·xH2O,通过元素分析、红外、核磁共振、X射线粉末衍射等手段对其进行了表征,提出了该类三维层柱超分子配合物的结构模型,并探讨了反应机理.  相似文献   

7.
由2,2,′,2"-三氨基三乙胺(tren)与N-氧化吡啶醛经席夫碱型缩合,然后还原C=N双键形成的产物为配体(L1),合成了一系列新三角架式过渡金属配合物:[ML12+[M=Mn(Ⅱ)、Ni(Ⅱ)和Zn(Ⅱ)]。利用元素分析、红外光谱、电子光谱和室温磁化率对配合物的结构和性质进行了研究。  相似文献   

8.
研究了1-芳基-4-乙氧羰基-5-氨基-1,2,3-连三唑(1)同甲酰胺、异氰酸磺酰氯以及内酰亚胺醚等的反应,制得5-H-1-芳基-1,2,3-连三唑[4,5-e]嘧啶-4-酮(2a-c)、5-N-甲基-1-芳基-1,2,3-连三唑[4,5-e]嘧啶-4-酮(3a-c)、1-芳基-4-乙氧羰基-5-脲基-1,2,3-连三唑(4a,b)、5-H-1-芳基-1,2,3-连三唑[4,5-e]嘧啶-4,6-二酮(5_(a,b))、1-苯基-1,2,3-连三唑[4,5-e]哌啶[1,2-b]嘧啶-4-酮(6a)、1-苯基-1,2,3-连三唑[4,5-e]氢化吖辛因[1,2-b]嘧啶-4-酮(7a),并经元素分析、红外、核磁共振以及质谱等方法确认了它们的结构,初步筛选了其代表特的生物活性.  相似文献   

9.
3-芳基-5,6-二氢噻唑并[2,3-C]均三唑和3-芳基-6,7-二氢均三唑并[3,4-b][1,3]噻嗪的合成王忠义,史海健,史好新(安徽师范大学化学系,芜湖241000)张自义(兰州大学化学系)三唑类化合物具有相当广泛的生物活性,如:抗菌、抗痉...  相似文献   

10.
1,3,4-二唑类化合物具有广泛的生物生理活性,如杀菌[1]、除草[2]、杀虫[3]和消炎[4]等,而2,5-二芳基-1,3,4-二唑类化合物一般具有昆虫生长调节活性,1980年美国Dow公司报道了2,5-双(2,4-二氯苯基)-1,3,4-二...  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

14.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

17.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

18.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

19.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

20.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  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