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1.
C~6~0O异构体的研究   总被引:2,自引:0,他引:2  
本文用臭氧氧化C~6~0的苯溶液,用HPLC分析产物,室温下氧化产物只得到一个C~6~0O异构体组分峰。低温下产物得到两个C~6~0O异构体组分峰。多出的一个峰经实验与理论的研究,表明它很可能是异构体C~6~0O(C~s)。  相似文献   

2.
C~6~0, C~7~0的烷基化   总被引:1,自引:0,他引:1  
本文利用低价稀土化物(S~mI~2或YbI~2)与C~6~0、C~7~0及卤代烃(烯丙基溴、氯苄)的混合溶液反应,制得烯丙基化、苄基化的富勒烯。发现与C~6~0相接的苄基数可以从1到14,验证了Krusic等人的结果。此外,还发现C~6~0可以进行烯丙基化,得到(CH~2=CHCH~2)~nC~6~0(n=1-10),C~7~0可以进行苄基化,C~7~0上至少可以接13个苄基,实验证明这类反应是对富勒烯进行烷基化的一种简便、有效的方法。  相似文献   

3.
用INDO系列方法对双笼氧化物C~1~2~0O进行了理论研究,结果表明:双笼氧化物C~1~2~0O的形成缓解了C~6~0O中环氧三元环的角张力,并形成了呋喃型五元环将两碳笼连接在一起。两碳笼的直接键连使两笼距离较近,有较弱的相互作用,但仍各自表现一定的独立性,C~1~2~0O可发生分解生成新的化合物,C~1~2~0O的电子光谱与母体分子C~6~0相似。  相似文献   

4.
王一波 《化学学报》1996,54(12):1165-1169
在MNDO-PM3方法优化的分子结构基础上, 用Hartree-Fock/6-31G从头计算法研究了D2点群手性C~7~6稳定结构的分子静电势, 获得了过C~7~6对称中心的三个正交平面XY, XZ和YZ上的平面静电势图和径向静电势图, 并与C~6~0和C~7~0做了对比分析。  相似文献   

5.
用INDO系列方法研究了C~6~0SiH~2的两种结构: 一是SiH~2加在两个六元环之间的键上形成C~2~v构型; 另一是SiH~2加在一个五元环和一个六元环之间的键上形成C~s构型。从总能量和LUMO-HOMO能级差看, C~6~0SiH~2的稳定结构应是C~2~v构型, 其中桥C(15)-C(30)的键长为0.1508nm, 键序为0.9369, 说明不开环, 形成类环丙烷结构。文中计算了两种构型的电子吸收光谱和NMR谱, 此类计算是基于对C~6~0SiH~2的等电子体C~6~0O和C~6~0CH~2的研究之上, 且后两者的研究结果与实验相一致。  相似文献   

6.
不同有机溶剂中C~6~0溶解度与温度的关系   总被引:2,自引:0,他引:2  
本文测定了温度280K以上C~6~0在一些有机溶剂中的溶解度与温度的依赖关系,发出280K以上C~6~0在正己烷、甲苯、二甲苯中溶解度随温度上升而减小, 表现出放热的溶解过程。与此相反, 在环己烷中C~6~0的溶解度却有所不同, 随着温度的升高而增大, 表现出吸热的溶解过程。  相似文献   

7.
异质富勒烯C~5~9Si与C~6~9Si的理论研究   总被引:4,自引:0,他引:4  
利用MNDO,AM1和PM3半经验量子化学计算方法对硅杂富勒烯C~5~9Si和C~6~9Si进行了系统的理论研究.计算了稳定构型、生成热、前沿轨道能级差、电离势、电子亲和势、绝对电负性和整体硬度.结果表明,硅杂富勒烯的稳定性虽然低于全碳富勒烯,但也具有相当的稳定性.C~5~9Si的稳定性比已经合成的C~5~8X~2(X=B,N)高,C~6~9Si与C~7~0的稳定性差异也很小,因此在适宜条件下文中所讨论的硅杂富勒烯是应该能够合成的.在C~6~9Si各异构体中,取代位置在赤道的异构体具有最低的能量和最大的前沿轨道能级差,也是最稳定的异构体.与全碳勒烯C~6~0和C~7~0相比,C~5~9Si和C~6~9Si具有较小的电离势和电子亲和势,表明硅杂富勒烯容易被氧化,而被还原的难度要些,但是仍容易发生还原反应而生成负离子.因此硅原子的掺杂能够使富勒烯的氧化还原性能得以改善.C~5~9Si和C~6~9Si更容易与亲电试剂反应,而发生亲核反应的活性要相对小一些.硅杂富勒烯C~5~9Si和C~6~9Si的绝对电负性和硬度都小于相对应的全碳富勒烯,对电子的束缚力要相对小一些。  相似文献   

8.
C~6~0-甲苯衍生物的制备及光谱特性研究   总被引:5,自引:0,他引:5  
沈悦  张建成  顾峰  邵洁  严继康  吴文彪 《化学学报》1999,57(9):1034-1037
以C~6~0和甲苯为原料,选择适当的催化反应条件,制备了C~6~0-甲苯衍生物。产物经紫外可见光谱和H质子核磁共振谱测定,推测了产物结构和反应机理。对不同反应时间产物光致发光光谱的特性进行研究,并与C~6~0发光光谱比较,室温下观测到峰值位于460nm附近递增的光致发光现象。  相似文献   

9.
C~4~0, C~4~0^+, Nb@C~4~0^+, NbC~3~9^+, Nb@C~4~0H~4^+的 量子化学研究   总被引:1,自引:0,他引:1  
用量子化学从头计算方法研究了C~4~0,C~4~0^+,Nb@C~4~0^+,NbC~3~9^+,Nb@C~4~0H~4^+的几何构型、电子结构和C~2~8一样,C~4~0(T~d)基态也为^5A~2态,笼骨架上具有四个悬挂键。计算结果表明C~4~0和C~4~0^+比NbC~3~9^+和Nb@C~4~0^+稳定,与实验结果一致。  相似文献   

10.
用量子化学从头计算方法研究了C~4~0,C~4~0^+,Nb@C~4~0^+,NbC~3~9^+,Nb@C~4~0H~4^+的几何构型、电子结构和C~2~8一样,C~4~0(T~d)基态也为^5A~2态,笼骨架上具有四个悬挂键。计算结果表明C~4~0和C~4~0^+比NbC~3~9^+和Nb@C~4~0^+稳定,与实验结果一致。  相似文献   

11.
自由基CN、CH、H在燃烧化学、大气化学、天体发光、环境污染等方面占有极为重要的地位,对于这些自由基发光及形成动力学机理的探讨,无疑是重要的.近年来,人们利用亚稳态惰性原子与膨化物碰撞传能,探讨了CN(AB-+X)的化学发光[‘一、发现亚稳态的Ar(‘几,。)原子与H  相似文献   

12.
Treatment of [[Ru(P(OCH(3))(3))(2)(CH(3)CN)(3)](2)(mu-S(2))](CF(3)SO(3))(4) (1), which is prepared by the reaction of [[RuCl(P(OCH(3))(3))(2)](2)(mu-S(2))(mu-Cl)(2)] (2) with 4 equiv of AgCF(3)SO(3), with terminal alkenes such as 1-pentene, allyl ethyl ether, allyl phenyl ether, 1,4-hexadiene, and 3-methyl-1-butene, resulted in the formation of complexes carrying a C(3)S(2) five-membered ring, [[Ru(P(OCH(3))(3))(2)(CH(3)CN)(3)](2)[mu-SCH(2)CH(2)CR(1)R(2)S]](CF(3)SO(3))(4) (3, R(1) = CH(2)CH(3), R(2) = H, 40%; 4, R(1) = OCH(2)CH(3), R(2) = H, 60%; 5, R(1) = OC(6)H(5), R(2) = H, 73%; 6, R(1) = CH=CHCH(3), R(2) = H, 48%; 7, R(1) = R(2) = CH(3), 40%). Reaction of 1 with methylenecycloalkanes was found to give several different types of products, depending on the ring size of the substrates. A trace of [[Ru(P(OCH(3))(3))(2)(CH(3)CN)(3)](2)[mu-SCH(CH(2)CH(2))CH(CH(3))S]](CF(3)SO(3))(4) (9) having a C(2)S(2) four-membered ring to bridge the two Ru atoms was obtained by the reaction of 1 with methylenecyclobutane, whereas the reaction with methylenecyclohexane gave [[Ru(P(OCH(3))(3))(2)(CH(3)CN)(3)](2)[mu-S(CH(2)(C=CHCH(2)CH(2)CH(2)CH(2))S)](CF(3)SO(3))(3) (10) in 69% yield via C-S bond formation and elimination of a proton. Throughout these reactions with alkenes giving a variety of products, the activation of the allylic C-H bond is always the essential and initial key step.  相似文献   

13.
A variety of inter- and intramolecular dehydration was found in the reactions of [[Ru(P(OCH(3))(3))(2)(CH(3)CN)(3)](2)(mu-S(2))](CF(3)SO(3))(4) (1) with hydroxyl substituted alkenes and alkynes. Treatment of 1 with allyl alcohol gave a C(3)S(2) five-membered ring complex, [[Ru(P(OCH(3))(3))(2)(CH(3)CN)(3)](2)[mu-SCH(2)CH(2)CH(OCH(2)CH=CH(2))S]](CF(3)SO(3))(4) (2), via C-S bond formation after C-H bond activation and intermolecular dehydration. On the other hand, intramolecular dehydration was observed in the reaction of 1 with 3-buten-1-ol giving a C(4)S(2) six-membered ring complex, [[Ru(P(OCH(3))(3))(2)(CH(3)CN)(3)](2) [mu-SCH(2)CH=CHCH(2)S]](CF(3)SO(3))(4) (3). Complex 1 reacts with 2-propyn-1-ol or 2-butyn-1-ol to give homocoupling products, [[Ru(P(OCH(3))(3))(2)(CH(3)CN)(3)](2)[mu-SCR=CHCH(OCH(2)C triple bond CR)S]](CF(3)SO(3))(4) (4: R = H, 5: R = CH(3)), via intermolecular dehydration. In the reaction with 2-propyn-1-ol, the intermediate complex having a hydroxyl group, [[Ru(P(OCH(3))(3))(2)(CH(3)CN)(3)](2)[mu-SCH=CHCH(OH)S]](CF(3)SO(3))(4) (6), was isolated, which further reacted with 2-propyn-1-ol and 2-butyn-1-ol to give 4 and a cross-coupling product, [[Ru(P(OCH(3))(3))(2)(CH(3)CN)(3)](2)[mu-SCH=CHCH(OCH(2)C triple bond CCH(3))S]](CF(3)SO(3))(4) (7), respectively. The reaction of 1 with diols, (HO)CHRC triple bond CCHR(OH), gave furyl complexes, [[Ru(P(OCH(3))(3))(2)(CH(3)CN)(3)](2)[mu-SSC=CROCR=CH]](CF(3)SO(3))(3) (8: R = H, 9: R = CH(3)) via intramolecular elimination of a H(2)O molecule and a H(+). Even though (HO)(H(3)C)(2)CC triple bond CC(CH(3))(2)(OH) does not have any propargylic C-H bond, it also reacts with 1 to give [[Ru(P(OCH(3))(3))(2)(CH(3)CN)(3)](2)[mu-SCH(2)C(=CH(2))C(=C=C(CH(3))(2))]S](CF(3)SO(3))(4) (10). In addition, the reaction of 1 with (CH(3)O)(H(3)C)(2)CC triple bond CC(CH(3))(2)(OCH(3)) gives [[Ru(P(OCH(3))(3))(2)(CH(3)CN)(2)][mu-S=C(C(CH(3))(2)OCH(3))C=CC(CH(3))CH(2)S][Ru(P(OCH(3))(3))(2)(CH(3)CN)(3)]](CF(3)SO(3))(4) (11), in which one molecule of CH(3)OH is eliminated, and the S-S bond is cleaved.  相似文献   

14.
Various copper(I) and copper(II) derivatives, both "simple" ones (copper acetate, perchlorate and a complex with CH3CN) and compounds containing N,O-chelating ligands, catalyse very efficient (turnover numbers attain 2200) oxidation of saturated hydrocarbons with peroxyacetic acid (PAA) or tert-butyl hydroperoxide (TBHP) in acetonitrile solution at 60 degrees C. Alkyl hydroperoxide, alcohol and ketone are formed, the main product being an alkyl hydroperoxide in the oxidation with PAA and an alcohol for the case of TBHP. It has been proposed that the oxidation with PAA is induced via the attack of species r* [HO* or CH3C(=O)O*] on the alkane, RH. A competitive attack of r* on the solvent, CH3CN, also occurs. It has been assumed that in the case of the reaction catalysed by complex Cu(CH3CN)4BF4, copper is present mainly in the form of Cu+ cation, and the rate-limiting step of the oxidation process is the formation of r* via reaction (1): CH3C(=O)OOH + Cu+ --> CH3C(=O)O* + HO- + Cu2+ or/and CH3C(=O)OOH + Cu+ --> CH3C(=O)O- + HO* + Cu2+ with initial rate W1 = k1[PAA][Cu(CH3CN)4BF4] and k1 = 1.7 mol(-1) dm3 s(-1) at 60 degrees C. The activity of the Cu-catalyst is dramatically changed on a small modification of N,O-chelating ligands in the catalyst.  相似文献   

15.
A series of carboxylate-substituted trinudear molybdenum dus-ter compounds formulated as Mo3S4(DTP)3(RCO2)(L), where RffiH, CH3, C2H5, CH2Cl, CCl3, R^1C6H4(R^1 is the group on the benzene ring of aromatic carboxylate ), L=pyridine,CH3CN, DMF, have been synthesized by the ligand substitu-tion reaction. The dissociation of the loosely-coordinated ligand L from the cluster core was studied by ^31p NMR. The dissocia-tion process of L is related to the solvent, temperature, and acidity of carboxylate groups, so as to affect the solution struc-ture and reactive properties of the duster. The long-distance in-teraction between ligands RCO2 and L is transported by Mo3S4 core.  相似文献   

16.
报道了C60与1,3-丙二胺和N,N-二甲基-1,3-丙二胺的加合反应,反应产物未经预先离子化处理直接用ESL-MS进行检测。由于反应产物从甲苯溶液中析出,避免了生成多胺基加合物,产物以单加成物为主。当加合反应在空气氛下进行时,有加合氧的产物C60On(NH2—CH2CH2CH2NR2)m(R=H,CH3)存在。实验发现:N,N-二甲基-1,3-丙二胺比1,3-丙二胺更容易与C60发生多胺基加成和氧加成反应。通过控制反应条件可制备C60二胺的单加成产物。  相似文献   

17.
The title compound was synthesized by reaction of Cu(ClO4)2, picolinic acid and carbamide in C2H5OH/CH3CN solution, and characterized by single-crystal X-ray diffraction. It crystallizes in the orthorhombic system, space group Pbca with a=14.0481(8), b=9.0130(5), c=18.626(1)?, V=2358.3(2)?3Z=4, Dx=1.771g·cm-3, μ=1.235mm-1 and F(000)=1276. The final R factor is 0.0440 for 1434 observed reflections. The X-ray analysis revealed that the copper(Ⅱ) atom is coordinated by two picolinic ligands in the equatorial plane, while the two oxygen atoms of perchlorate occupy the axial positions of octahedron with lengthened Cu-O distances, resulting in a 4+2 elongated octahedral environment. In the compound, there also exist two protonated carbamide cations for charge balance. CCDC: 195354.  相似文献   

18.
The very unusual case of copper-mediated chlorination of phenol rings under mild conditions at room temperature is reported. Reaction of the ligand 1,7-bis(2-hydroxyphenyl)-2,6-diaza-4-hydroxylheptane (H3L1) with CuCl2 in acetonitrile leads to either the formation of a tetranuclear copper(II) complex [Cu4(HL3)2(mu-Cl)2Cl2](CH3CN) (1) or a linear trinuclear complex [Cu3(HL1)2Cl2(CH3CN)2](CH3CN)2 (2), depending on the reaction conditions. Both compounds have been fully characterized, including the determination of their 3D structures by X-ray diffraction. The unprecedented tetranuclear compound 1 is constituted of a dichlorido-bridged dimer of di-mu-phenoxido-dinuclear species, whereas the trinuclear complex 2 presents a linear array of copper(II) ions, held together through di-mu-phenoxido bridges of the central and external ions. The magnetic susceptibility of the two compounds was investigated, revealing either very strong (J<-500 cm-1) or strong (J value around -370(1) cm-1) antiferromagnetic dominant interactions among the CuII ions for 1 and 2, respectively. The tetranuclear complex 1 is obtained, under dry conditions, through the in situ formation of ligand HL3 (H3L3=1,7-bis(2-hydroxy-5-chlorophenyl)-2,6-diaza-4-hydroxylheptane) by oxidative chlorination of (HL1)2-. In the presence of traces of water, 1 is partially hydroxylated at the ortho position of one of the phenyl rings. The use of trimethylorthoformate as the dehydrating agent prevents the formation of hydroxylated ligands. Several partly chlorinated/hydroxylated products (identified as H3L2) have also been obtained through slight variations of the synthetic procedures (presence or absence of water and/or triethylamine in the reaction mixtures). These partially chlorinated and/or hydroxylated coordination species are mutually isomorphous to either 1 or 2. Several "modified" ligands have been isolated and characterized by 1H NMR and MS, after reaction with sodium sulfide of the complexes formed.  相似文献   

19.
Cu(CH3COO)2 和4 氨基 3,5 二甲基 1,2,4 三氮唑反应制得标题化合物的单晶[Cu2(CH3COO)4(C4H8N4)2]·2CH3CN。晶体属三斜晶系 ,空间群 ,a=8.266(2),b=8.585(2),c=10.741(2) ,α=75.58(3),β=88.46(3),γ=86.35(3)°,V=736.7(3) 3 ,Z=1,Dc=1.509g·cm 3,F(000)=346,μ=1.502mm 1 。X 射线衍射结构分析表明 ,Cu2(CH3COO)4(C4H8N4)2 单元是中心对称的双核配合物 ,两个铜原子间距为2.698 。每个金属原子被围成四方锥的配位结构 ,四个乙酸根配体中最近的四个氧原子处在底面上[Cu O=1.965(3)~1.986(3) ] ,一个4 氨基 3,5 二甲基 1,2,4 三氮唑配体位于顶点位置Cu N=2.172 。  相似文献   

20.
1 INTRODUCTIONSince1980,manyV/Fe/Sheterometallicsulfurclustercompoundshavebeenreported.RauchfussetalobtainedtwokindsofV/Fe/Scompounds[1]using(CH3C5H4)2V2S4asanorganometallicligand,oneis(MeCp)2V2Fe2(NO)2S4withacubanelikestructureandanotheris(MeCp)2V2S4Fe(NO)2and(MeCp)2V2S4…  相似文献   

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