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1.
(η^5-C5H5)(η^5-C5H4R)TiCl2类化合物的新合成方法   总被引:1,自引:0,他引:1  
本文报道了取代环戊二烯基负离子与[(η~5-C_5H_5)TiCl_2]_2O反应生成(η~5-C_5H_5)(η~5-C_5H_4R)·TiCl_2的新方法。研究了取代环戊二烯基负离子的空间位阻和(η~5-C_5H_5)TiCl_3,[(η~5-C_5H_5)TiCl_2]_2O的结构以及反应温度对产物产率的影响。合成了七个新的(η~5-C_5H_5)(η~5-C_5H_4R)TiCl_2类型的化合物及七个相应的二氟化合物。  相似文献   

2.
陈寿山  姚文庆 《化学学报》1990,48(3):262-265
本文报道了取代环戊二烯基负离子与[(η^5-C5H5)TiCl2]2O反应生成(η^5-C5H5)(η^5-C5H4R).TiCl2的新方法. 研究了取代环戊二烯基负离子的空间位阻和(η^5-C5H5)TiCl3, [(η^5-C5H5)TiCl2]2O的结构以及反应温度对产物产率的影响. 合成了七个新的(η^5-C5H5)(η^5C5H4R)TiCl2类型的化合物及七个相应的二氟化合物。  相似文献   

3.
[LiDME][(η^5—C5H5)3Nd(μ—H Nd(η^5—C5H5)3]...   总被引:1,自引:0,他引:1  
孙益民  沈琪 《应用化学》1991,8(1):23-27
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4.
MoCl_5在HZSM-5和APO-5上没有发生“双聚”,沸石的酸性对MoCl_5负载量的影响大于孔结构。APO-5负载MoCl_5后,仅生成数量和强度都很小的B酸中心。Mo-ZSM-5沸石在MTG反应中有Mo和Al的表面迁移,负载的MoCl_5通过氧化-还原及水解等过程产生羟基,增加了ZSM-5沸石的B酸量,通过B酸-L酸中心的电子协同效应增加载体的B酸强度,调变了催化剂的酸性分布。  相似文献   

5.
MoCl5在HZSM-5和APO-5上的负载及调变作用   总被引:2,自引:1,他引:1  
朱建华 《催化学报》1993,14(4):294-299
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6.
The avermectins1 are a unique collection of naturally occurring macrocyclic lactones with broad spectrum of anthelmintic and insecticidal activities. Their remarkable biological activity and complex molecular architecture stimulated significant interest in the scientific community. Much research has been carried out on these compounds. Many derivatives of avermectin have much more bioactivities and have been commercially utilized2-5. Here we describe the synthesis of 5-deoxy-5-acyloxyimi…  相似文献   

7.
8.
Fast time-resolved infrared spectroscopic measurements have allowed precise determination of the rate of C-H activation of alkanes by Cp'Rh(CO) {Cp' = η(5)-C(5)H(5) or η(5)-C(5)Me(5); alkane = cyclopentane, cyclohexane and neopentane (Cp only)} in solution at room temperature and allowed the determination of how the change in rate of oxidative cleavage varies between complexes and alkanes. Density functional theory calculations on these complexes, transition states, and intermediates provide insight into the mechanism and barriers observed in the experimental results. Unlike our previous study of the linear alkanes, where activation occurred at the primary C-H bonds with a rate governed by a balance between these activations and hopping along the chain, the rate of C-H activation in cyclic alkanes is controlled mainly by the strength of the alkane binding. Although the reaction of CpRh(CO)(neopentane) to form CpRh(CO)(neopentyl)H clearly occurs at a primary C-H bond, the rate is much slower than the corresponding reactions with cyclic alkanes because of steric factors with this bulky alkane.  相似文献   

9.
The melting temperature, melting enthalpy, and specific heat capacities (C p) of 5′-deoxy-5′-iodo-2′,3′-O-isopropylidene-5-fluorouridine (DIOIPF) were measured using DSC-60 Differential Scanning Calorimetry. The melting temperature and melting enthalpy were obtained to be 453.80 K and 33.22 J g?1, respectively. The relationship between the specific heat capacity and temperature was obtained to be C p/J g?1 K?1 = 2.0261 – 0.0096T + 2 × 10?5 T 2 at the temperature range from 320.15 to 430.15 K. The thermal decomposition process was studied by the TG–DTA analyzer. The results showed that the thermal decomposition temperature of DIOIPF was above 487.84 K, and the decomposition process can be divided into three stages: the first stage is the decomposition of impurities, the mass loss in the second stage may be the sublimation of iodine and thermal decomposition process of the side-group C4H2O2N2F, and the third stage may be the thermal decomposition process of both the groups –CH3 and –CH2OCH2–. The obtained thermodynamic basic data are helpful for exploiting new synthetic method, engineering design, and commercial process of DIOIPF.  相似文献   

10.
Marken  Frank  Marx  Hans -W.  Englert  Ulli 《Structural chemistry》1994,5(3):177-181
The substituted sandwich complex crystallizes in monoclinic space groupP21/m withZ=2. Twinning to the (001) direction with the special conditionc */4a * = cos * causes systematic superposition of the reciprocal lattices of both domains and results in an apparent unit cell with double volume and the reflection condition (2h)kl, l=2n. The structure solution was obtained with the subset of intensity data for the predominant individuum and converged atR = 0.040,R w =0.046 for 832 independent observations and 122 variables. The molecules show disorder with respect to the crystallographic mirror plane. The structure is closely related to that of decamethylruthenocene.  相似文献   

11.
通过(η5-RC5H4)MCoFeS(CO)8(la:M=Mo,R=H;1b:M=Mo,R=MeO2C;lc:M=Mo,R=Me;1d:M=Mo,R=EtO2C;1e:M=W R=H)与Cp2Ni的等瓣置换反应合成了簇合物(η5-C5H5)(η5-RC5H4)MNiFeS(CO)5(2a:M=Mo,R=H;2b:M=Mo,R=MeO2C;2c:M=Mo,R=Me;2d:M=Mo,R=EtO2C;2e:M=W,R=H).进一步通过2a,b与Co2(CO)8以及2c,d与Fe2(CO)9的等瓣置换反应,分别合成了(η5-RC5H4)MoCoFeS(CO)8(la:R=H;1b:R=MeO2C)和(η5-C5H5)(η5-RC5H4)MoNiFe2S(CO)10(3a:R=Me;3b:R=EtO2C).新簇合物2c-e和3a,b的结构均经元素分析、IR及1H NMR谱学表征.此外,还对我们以前合成的一个3a,b类似物(η5-C5H5)(η5-MeO2CC5H4)MoNiFe2S(CO)10(3c)成功地进行了单晶结构分析.3c属单斜晶系,Cc(#9)空间群,晶胞参数a=1.0051(3)nm,b=1.5311(5)nm,c=1.7437 nm,β=105.5(3)°,Z=4.最终一致性因子R=0.025,Rw=0,033.  相似文献   

12.
使用二正丙胺(DPA)和二正丁胺(DBA)作结构导向剂合成出VPI-5和Si-VPI-5,并以二异丙胺(DIPA)为结构导向剂成功地合成出高结晶度的超大孔磷酸铝分子筛VPI-5,其XRD谱图中未检测出其他杂质峰.VPI-5分子筛不同于一般中微孔磷酸铝分子筛,合成条件极其苛刻,为此对原料组成、成胶条件、陈化时间和温度、晶化时间和温度、结构导向剂种类、pH等合成条件对VPI-5分子筛结晶度的影响作了较为详尽的研究,结果表明有机胺在晶化过程中具有结构导向作用,但不起空间填充作用,加有机胺前的陈化过程是必要的.  相似文献   

13.
5,5-Fulvalenedimanganesehexacarbonyl (dicymantrenyl) was acetylated and benzoylated by RC(O)Cl+AlCl3 in CH2Cl2, under conditions of the Friedel-Crafts reaction. The reaction involves both nonequivalent positions of the cyclopentadienyl rings to give mixtures of two isomeric ketones. When using an excess of the acetylating mixture, diacetyl derivatives of dicymantrenyl were obtained.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2017–2020, October, 1995.The authors are grateful to P. V. Petrovsky and E. V. Vorontsov (the NMR laboratory of the Institute of Organoelement Compounds, Russian Academy of Sciences) for recording1H NMR spectra.  相似文献   

14.
ZAPO-5和MnAPO-5分子筛大单晶的生长   总被引:2,自引:0,他引:2  
磷酸锌铝(ZAPO-5)和磷酸锰铝(MnAPO-5)分予筛是新型分子筛[1],由文献[1]可知UCC得到了粉末状的ZAPO-5和MnAPO-5分子筛,得到的ZAPO-5不仅是粉末状而且是不纯的,本文报道了ZAPO-5和MnAPO-5纯相大单晶的合成。  相似文献   

15.
<正> INTRODUCTION. The structure of the title compound has been determined as a part of our systematic studies on the structural chemistry of silver. CRYSTAL DATA. The compound AgSCN'C_5H_5N crystallized from a pyridine  相似文献   

16.
具有ZSM-5结构的含钛和含硼分子筛是催化性能良好的新型杂原子分子筛,可分别作为碳氢化合物的氧化反应[1]和制备高纯异丁烯的催化剂[2]。近年来,有关这2种分子筛的合成已见报道[1~4]。但其合成均采用碱性介质,成核和晶化都比较快,因此未能得到生长完美的杂原子ZSM-5型分子筛大单晶。  相似文献   

17.
5-Deoxy-5-[18F]fluoro-adenosine was synthesised by nucleophilic radiofluorination reactions of 5-deoxy-5-haloadenosines. The homogeneous isotope exchange in 5-deoxy-5-fluoro-adenosine was also investigated. The conversion of these reactions was found to be rather low and depends on the strength of the halogen-carbon bond: 0.248% for chloride-, 0.488% for bromide- and 1.070% for iodide-derivative; there was no reaction observed in the case of fluoro-compound.  相似文献   

18.
Thereactionsof6,6-dialkylfulveneswithactiveorganometal(Li,Na,Mg)reagentshavebeensystematicallystudiedin0urlab0ratory.Thesereactionsprovideapracticalpathwayforthepreparationofcyclopentadienylanions,inparticularthosewithbulkysubstituents,whichcanbereadilycoordinatedwithtransitionmetalhalidestopr0ducesubstitutedmetall0cenes(Ti,Zr,Fe)1.6,6-Dimethylfulvene0r6,6-pentamethylenefulvenecaneasilyundergoexocyclicdoublebondadditionreactionsbythetreatmentof(substituted)phenyllithiumt0givearylsubstitutedc…  相似文献   

19.
本文通过η^5-Bz~5C~5MNa与氧化偶联试剂Fe~2(SO~4)~3/HOAC/H~2O的反应合成了含η^5-五苄基环戊二烯基配体的两个金属-金属单键化合物[η^5-Bz~5C~5(CO)~3M]~2 (1: M=Mo; 2: M=W) , 产率分别为45%和19% . 1 在沸腾的甲苯中可进一步脱碳而以98%的产率生成金属-金属叁键化合物[η^5-Bz~5C~5(CO)~2Mo]~2 (3).1~3的结构均经碳氢分析, IR, ^1H NMR 和MS鉴定. 3的结构尚被单晶X射线衍射分析确证 .  相似文献   

20.
标题配合物是以THF作溶剂,通过(C_5H_5)_2NdCl·ZLiCl和甲基萘钠的还原反应合成的。其晶体属单斜晶系,P 2/c空间群,晶胞参数α=9.235(2)A,b=11.695(2)A,c=20.810(3)A,β=92.88(1)°,Z=2。研究结果表明,标题配合物由相互不相联的〔Li3DME〕~ 和〔(η~5-C_5H_5)_3Nd(μ-H)Nd(η~5-C_5H_5)_3〕~-离子对组成。阳离子中,Li原子与由3个DME提供的6个O原子配位,形成八面体构型,Li—O平均键长为2.116A;阴离子中,2个Nd原子不直接键合,系通过桥H联接,Nd—H=2.19A。此外,每个Nd原子各有3个C_5H_5~-与之配位,Nd—C平均键长为2.812A。  相似文献   

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