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1.
以四苯基环戊二烯酮为起始原料,经过八步连续反应,成功地合成了3个炔桥联不对称五苯基取代双二茂铁衍生物Fc''-C≡C-Fc(1)、Fc''-C≡C-C≡C-Fc(2)和Fc''-C≡C-C≡C-Fc''(3)(Fc''=五苯基二茂铁基,Fc=二茂铁基)。在设计合成双二茂铁衍生物的过程中,首先经过4步反应,制备出已知化合物Fc''-H(4),再连续进行3步反应,分别得到3个中间化合物Fc''-COCH35),Fc''-CCl=CHCHO(6)和Fc''-C≡CH(7),最后利用偶联反应,得到目标化合物1~3。利用X射线单晶衍射和循环伏安法,测定了化合物1、25、7的晶体结构,研究了化合物1~7的电化学性质。研究结果表明,分子的C-H…π键相互作用和空间位阻是导致化合物12分子中Fc''和Fc基空间排布取向不同的主要原因。当二茂铁的一个环戊二烯环上引入5个苯取代基时,铁中心的氧化还原电位将升高(Epa(Fc''-H)=0.658 V,Epa(Fc-H)=0.511 V)。与已知化合物Fc-C≡C-Fc(ΔE=0.215 V)和Fc-C≡C-C≡C-Fc(ΔE=0.134 V)相比,化合物1~3的氧化电位差值(ΔE)均有不同程度地提高(ΔE1=0.236 V;ΔE2=0.170 V;ΔE3=0.146 V)。将1与Fc-C≡C-Fc,2与Fc-C≡C-C≡C-Fc和3进行比较发现,当炔桥两端连接不同的基团Fc''和Fc时,其氧化电位差值(ΔE)将明显提高。  相似文献   

2.
价电子能级连接性指数及其应用   总被引:46,自引:2,他引:44  
价电子能级连接性指数( fE)被定义为: fE=Σ(mi·mj…)-0.5,m为价电子能级值。其中0、1阶指数公式分别为: 0E=Σ(mi)-0.51E=Σ(mi·mj)-0.50E1E与化合物的总键能(ΔE)、晶格能(U)、标准生成焓(ΔfH?m)以及非金属氢化物的pKa呈现高度相关性。它们的线性回归方程为:ΔE=-48.0095+1402.94631E,r=0.9474, U=-328.0770+1541.9351 1E, r=0.9801,-ΔfH?m=-266.9299+1324.6461 1E, r=0.9509, pKa=-20.9723+28.1756 1E, r=0.98884, pKa=-14.6102-7.835 0E+40.6461 1E, R=0.9933。mfE具有物理意义明确、计算方法简单等优点,而且预测结果令人满意。  相似文献   

3.
基于一系列二氰根铬与[Cu(cyclam)](ClO4)2反应合成了3个氰根桥联Cr-Cu-Cr三核配合物[Cu(cyclam)][Cr(bpmb)(CN)2]2·4H2O(1)(cyclam=1,4,8,11-四氮杂环十四,bpmb2-=1,2-二(2-吡啶甲酰胺基)-4-甲基苯),[Cu(cyclam)][Cr(bpdmb)(CN)2]2(2)(bpdmb2-=1,2-二(2-吡啶甲酰胺基)-4,5-二甲基苯)和[Cu(cyclam)][Cr(bpClb)(CN)2]2·4H2O(3)(bpClb2-=1,2-二(2-吡啶甲酰胺基)-4-氯苯)。单晶衍射结果表明:3个化合物是结构类似的中性三核配合物,均含有氰根桥联的Cr(Ⅲ)-CN-Cu(Ⅱ)-NC-Cr(Ⅲ)连接;磁性研究表明:氰根桥在Cr和Cu离子间传递弱的铁磁耦合作用,基于自旋哈密顿算符Ĥ=-2JCrCuŜCuCr1Cr2)拟合得到它们的磁耦合常数分别是JCrCu=1.53(2) cm-1(1),0.45(1) cm-1(2)和0.73(2) cm-1(3)。  相似文献   

4.
使Zn(OAc)2·2H2O或Cd(OAc)2·2H2O与邻羧基苯甲酰二茂铁钠(o-OOCC6H4COFcNa;Fc=(η5-C5H5)Fe(η5-C5H4))和1,10-邻菲咯啉(phen)在甲醇中反应,合成了含有混合配体的单核配合物[Zn(o-OOCC6H4COFc)2(phen)(H2O)]·CH3OH (1)和双核配合物{[Cd(η2-o-OOCC6H4COFc)( μ2-o-OOCC6H4COFc)(phen)]·CH3OH2·H2O}2 (2)。晶体结构表明:在1中,单核的结构单元通过分子间氢键形成了一维的长链结构;在2中,o-FcCOC6H4COO-以及phen均双齿螯合中心Cd(II)离子,随后在o-FcCOC6H4COO-的双齿桥联下,形成一个双核结构。研究了这2个配合物在DMF溶液中的电化学性能。  相似文献   

5.
配体C9H7R(R=CH2CH2CH3 (1),CH2(CH3)2 (2),C5H9 (3),CH2C6H5 (4),CH2CH=CH2 (5))分别与Ru3(CO)12在二甲苯或庚烷中加热回流,得到了6个双核配合物[(η5-C9H6R)Ru(CO)(μ-CO)]2(R=CH2CH2CH3 (6),CH2(CH3)2 (7),C5H8 (8),CH2C6H5 (9),CH2CH=CH2 (10))和[(η5-C9H6)(H3CH2C)CHCH(CH2CH3)(η5-C9H6)] [Ru(CO)(μ-CO)]2 (11).通过元素分析、红外光谱、核磁共振氢谱对配合物的结构进行了表征,并用X-射线单晶衍射法测定了配合物6,9,1011的结构.  相似文献   

6.
分别以E-3-[4-(羧甲氧基)-苯基]丙烯酸(H2L1)和E-3-[4-(羧甲氧基)-苯基]丙烯酸(H2L2)为主配体,合成了3种钴(Ⅱ)配位聚合物:[Co(L1)(bpp)]n(1),{[Co(μ3-OH)2(L2)4(bpy)2(H2O)4]·12H2O}n(2)和[Co(L2)(bpy)]n(3)(bpp:1,3-二吡啶基丙烷,bpy:4,4-联吡啶)。通过元素分析、红外光谱、X射线粉末和单晶衍射对其进行了结构表征。结果表明钴(Ⅱ)离子在这3种配合物中具有不同的配位环境,导致3种配合物具有不同的晶体结构和磁性特征。  相似文献   

7.
利用二烃基氧化锡和α-萘氧乙酸按1∶1反应,合成了8种新的有机锡化合物,{[(n-C4H9)2Sn(OOCCH2OC10H7)]2O}2(R= nBu 1,2-ClC6H4CH2 2,3-ClC6H4CH2 3,4-ClC6H4CH2 4,2-FC6H4CH2 5,3-FC6H4CH2 6, 4-FC6H4CH2 7, 4-NCC6H4CH2 8)。用元素分析、IR、 1H NMR对其结构进行了表征,并测定了化合物{[(n-C4H9)2Sn(OOCCH2OC10H7)]2O}2 (1)的晶体结构。该化合物晶体属三斜晶系,空间群P1,a=11.974(7) nm,b=1.360 5(9) nm,c=1.386 5(9) nm,α=103.940(9)°,β=104.876(8)°,γ=99.807(9)°,Z=1,V=2.053(2) nm3Dc=1.431 Mg·m-3,μ=1.261 mm-1F(000)=900,S=1.004,R1=0.061 0,wR2=0.151 9。结果表明,化合物1是以Sn2O2为中心的中心对称二聚体结构,内环锡和外环锡原子均为五配位的畸变三角双锥构型。  相似文献   

8.
吕赟  张登  范新蓉  万洪祥  许岩 《无机化学学报》2013,29(12):2623-2630
通过溶剂热合成技术,我们得到了两种新的二维层状稀土硫酸盐:[Tb2(SO4)5][(CH3)2NH2]4(1)和[Y2(SO4)5][(CH3)2NH2]4(2),并通过X-射线衍射、元素分析及红外、热重对化合物进行了表征。两种化合物都属于三斜晶系,P1空间群。其中化合物1a=0.988 7(3) nm,b=1.106 1(3) nm,c=1.535 4(4) nm,α=70.45(4)°,β=75.12(3)°,γ=67.11(3)°,Z=2;化合物2:a=0.981 6(5) nm,b=1.100 1(5) nm,c=1.528 6(8) nm,α=70.44(6)°,β=75.45(6)°,γ=67.48(6)°,Z=2。通过对晶体结构进行表征我们发现两种化合物都含有二维层状无机骨架结构,该层由2种不同类型的双链和十二元环构成。我们还对化合物1的荧光性质进行了研究,其在369 nm的激发波长下表现出了Tb3+的特征发射。  相似文献   

9.
以三齿吡唑-三嗪(类蝎型)化合物2,4-二(3,5-二甲基吡唑)-6-二乙基胺-1,3,5-三嗪(bpz*eaT)为配体,在无水乙醇和甲醇溶剂中,合成了2个配合物Cu2(mpz*eaT-EtO)2(N3)2Cl2(1)和Cu2(mpz*eaT-MeO)2(N3)4(2)(mpz*eaT-EtO:2-(3,5-二甲基吡唑)-4-乙醇-6-二乙基胺-1,3,5-三嗪;mpz*eaT-MeO:2-(3,5-二甲基吡唑)-4-甲醇-6-二乙基胺-1,3,5-三嗪)。通过元素分析、红外光谱、紫外光谱、热重分析以及X-ray单晶衍射方法对配合物进行了表征,并分析了其光谱及结构特征。晶体结构表明,配合物1属于三斜晶系,P1空间群,a=0.9949(2)nm,b=1.0216(2)nm,c=1.1480(2)nm,α=115.11(3)°,β=106.99(3)°,γ=100.39(3)°,V=0.9460(3)nm3,Z=1;配合物2属于单斜晶系,P21/c空间群,a=1.5464(5)nm,b=1.4008(5)nm,c=0.8905(3)nm,β=103.227(5)°,V=1.8779(10)nm3,Z=2。配合物12中的中心铜原子均为五配位,形成扭曲的四角锥构型。  相似文献   

10.
在DDQ/PPh3作用下,以2-异丙基苯甲酸或水杨酸为原料,在温和条件下以较高的收率合成、分离得到两个化合物(2)和(3)。化合物(2)和(3)与苯胺在氯仿中加热回流可分别转化为酰胺类化合物(4)和(5)。所有化合物通过元素分析、质谱、核磁共振进行了表征,并解析了化合物(2)和(3)的X-衍射单晶结构。化合物1,2-二(2-异丙基苯甲酸)-2,3-二氰-5,6-二氯苯(2)晶体属单斜晶系,空间群P21/c,其晶胞参数为:a=1.2875(3)nm,b=1.5186(2)nm,c=1.5726(3)nm,β=122.23(3)°,V=2.6010(1)nm3,Dc=1.331g·cm-3,Z=4,F(000)=1080,R1=0.0572,wR2=0.1260;化合物1,2-二(2-羟基苯甲酸)-2,3-二氰-5,6-二氯苯(3)晶体属三斜晶系,空间群P1,其晶胞参数为:a=0.87776(16)nm,b=1.13111(15)nm,c=1.18639(17)nm,α=69.290(2)°,β=89.409(3)°,γ=67.878(2)°,V=1.0104(3)nm3,Dc=1.542g·cm-3,Z=2,F(000)=476,R1=0.0383,wR2=0.0931。强π-π堆积作用和分子间氢键将化合物(2)和(3)组装成稳定的三维结构。  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.
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   

20.
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   

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