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221.
1978年Lappert等人首先合成了二(三甲硅基环戊二烯基)稀土氯化物[Li(THF)](Me_3SiC_5H_4)_2LnCl] (Ln=Y,Yb)和Yb(C_5H_4SiMe_3)_2。三甲硅基环戊二烯基稀土二氯化物,则未见报导.采用三甲硅基环戊二烯作为合成稀土金属有机化合物的配体,不仅可以增加所合成的稀土化合物在非极性溶剂中的溶解度,而且在反应过程中可以减小歧化反应的发生,得到所要求的产物.我们探索了三甲硅基环戊二烯基稀土二氯化物的合成,并对所得到的产物进行了鉴定. 相似文献
222.
The 1,1′-ring-substituted vanadocene dichlorides [V(η5-C5H4R)2Cl2] (R = CMe3, SiMe3, SiEt3) have been prepared from VCl4 and the appropriate lithiated cyclopentadiene, C5H4RLi, in 1 : 2 ratios. All complexes were characterized by elemental microanalysis and IR spectroscopy. The crystal structures of [V(η5-C5H4SiMe3)2Cl2] 3 and the parent compound [V(η5-C5H5)2Cl2] 1 have been determined by X-ray diffraction and are in accordance with expectations. Compound 1 crystallizes with two crystallographically independent molecules in its monoclinic unit cell. These two molecules are quite similar in their essential structural features. Compound 3 crystallizes in the triclinic space group P1 . The trimethylsilylcyclopentadienyl rings are bound in a staggered relative orientation. 相似文献
223.
孙文华 State Key Laboratory of Engineering Plastics The Center for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing China 《高分子科学》2003,(4):453-457
8-Aminoquinoline nickel dichloride and bis(cyclopentadienyl)zirconium dichloride (Cp_2ZrCl_2) were supportedsimultaneously on silica to produce branched polyethylene successfully by combined polymerization. The supportedpolymerization results showed that the molecular weight of polyethylene increased while the molecular weight distributionbecame wider and the molecular chains of oligomers remaning in the final solution became shorter as compared to theoligomers obtained in polymerization processes with pure 8-aminoquinoline nickel dichloride catalysis, as well as theCp_2ZrCl_2 and nickel combination system. With decreasing amount of Ni catalyst in the supported catalyst, the molecular chains of oligomers in the resulting solution became shorter, while α-olefin selectivity increased. 相似文献
224.
Solubility of titanocene dichloride in supercritical propane 总被引:1,自引:0,他引:1
The solubilities of titanocene dichloride in supercritical propane had been investigated under the pressure range from 10 to 35 MPa using a flow phase equilibrium apparatus at temperatures of 383.15, 388.15, 393.15, 398.15, 403.15, and 408.15 K, respectively. The measured solubilities exhibited a clear dependence on temperature and pressure and could be correlated with the Peng–Robinson equation of state in the fugacity coefficient expression with fairly good accuracy. 相似文献
225.
H. L. Singh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1768-1778
Reaction of tin(II) chloride and dimethyltin dichloride with Schiff bases derived from S-benzyldithiocarbazate leads to the formation of a new series of tin(II) and organotin(IV) complexes of general formula SnCl 2 .L and Me 2 SnCl 2 .L (where L = Schiff bases are derived from the condensation of S-benzyldithiocarbazate with heterocyclic aldehydes). An attempt has been made to prove the structures of the resulting complexes on the basis of elemental analysis, conductance measurements, molecular weight determinations, infrared, and multinuclear magnetic resonance ( 1 H, 13 C, and 119 Sn NMR) spectral studies. A few representative ligands and their tin complexes have also been screened for their antibacterial and antifungal activities and found to be quite active in this respect. 相似文献
226.
227.
Seyed Hossein Hosseini Reza Ansari Peymane Noor 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):1394-1401
Abstract Methyl phosphonic dichloride (MPDC) and dimethyl methyl phosphonate (DMMP) are two important organophosphorus compounds used in the preparation of many toxic organophosphorus compounds such as nerve agents. This paper deals with the application of polyaniline coated on a glass slide surface as a sensor for the detection of some of the stimulant nerve agents such as MPDC and DMMP. The sensing behavior of polyaniline films toward MPDC and DMMP vapors via electrical conductivity changes of the polymer film using the standard four-point probe technique was investigated. The effects of the chemical concentration and the polymer thickness on the conductivity and conductivity stability of the polymer were also studied. The vapors of nerve agent stimulants affect the PANi film by the p-doping mechanism and lead to an increase in the conductivity of the polymer. The response times of the PANi film to MPDC and DMMP vapors are very fast, and the conductivity of the polymer increases with the increase in the concentration of the samples. 相似文献
228.
Hongya Li Biao Yan Haixia Ma Xiangrong Ma Zhiyong Sun Yajun Ma 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(8):821-827
Bis(5‐amino‐1,2,4‐triazol‐4‐ium‐3‐yl)methane dichloride (BATZM·Cl2 or C5H10N82+·2Cl?) was synthesized and crystallized, and the crystal structure was characterized by single‐crystal X‐ray diffraction; it belongs to the space group C2/c (monoclinic) with Z = 4. The structure of BATZM·Cl2 can be described as a V‐shaped molecule with reasonable chemical geometry and no disorder, and its one‐dimensional structure can be described as a rhombic helix. The specific molar heat capacity (Cp,m) of BATZM·Cl2 was determined using the continuous Cp mode of a microcalorimeter and theoretical calculations, and the Cp,m value is 276.18 J K?1 mol?1 at 298.15 K. The relative deviations between the theoretical and experimental values of Cp,m, HT – H298.15K and ST – S298.15K of BATZM·Cl2 are almost equivalent at each temperature. The detonation velocity (D) and detonation pressure (P) of BATZM·Cl2 were estimated using the nitrogen equivalent equation according to the experimental density; BATZM·Cl2 has a higher detonation velocity (7143.60 ± 3.66 m s?1) and detonation pressure (21.49 ± 0.03 GPa) than TNT. The above results for BATZM·Cl2 are compared with those of bis(5‐amino‐1,2,4‐triazol‐3‐yl)methane (BATZM) and the effect of salt formation on them is discussed. 相似文献
229.
Tadatomi Nishikubo Atsushi Kameyama Tomoko Yaguchi 《Journal of polymer science. Part A, Polymer chemistry》2000,38(21):4006-4012
Poly(cyanurate)s (P‐1–P‐4) containing triazine groups in the main chain and pendant chloromethyl groups in the side chain were synthesized by the polyaddition of bis(epoxide)s with 2,4‐dichloro‐6‐(diphenylamino)‐s‐triazine (DPAT) using quaternary onium salts as catalysts. The polyaddition of diglycidyl ether of bisphenol‐A (DGEBA) with DPAT proceeded smoothly in chlorobenzene at 100 °C for 12 h to give P‐1 with Mn = 19,000 in a 92% yield, when tetrabutylammonium chloride (TBAC) was used as a catalyst. However, no reaction occurred without a catalyst or with triethylamine alone under the same reaction conditions. Polyadditions of other bis(epoxide)s with DPTA also proceeded smoothly using 5 mol % of TBAC as a catalyst in chlorobenzene to produce corresponding polymers (P‐2≈P‐4) in high yields under similar reaction conditions. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4006–4012, 2000 相似文献
230.
2,6-Bis(methylenecyclopentadienyl)-pyridine-zirconocene and -hafnocene Dichloride; Formation and Crystal Structure of [C5H3N-2,6-(CH2? C5H4)2Zr(Cl)(OH2)[ZrCl6]] Pyridine bridged metallocene dichlorides of type C5H3N-2,6-(CH2? C5H4)2MCl2 (M = Zr ( 2 ), Hf ( 5 )) were synthesized. The presence of N → Zr interaction favours the formation of zirconocene cations. Traces of water cause the formation of the salt-like compound [C5H3N-2,6-(CH2? C5H4)2Zr(Cl)(OH2)]2[ZrCl6] 4 from 2 . The new compounds were characterized by 1H n.m.r., and mass spectroscopy. The X-ray crystal structure of 4 shows discrete cations and anions which are connected by H-bridges. 相似文献