新型大位阻取代茂钛,锆化合物的合成及其谱学性质

通过１－环庚烯基锂与６，６－二烷基富烯发生环外双键的加成反应形成的大取代茂锂试剂与ＭＣｌ４（Ｍ＝Ｔｉ，Ｚｒ）反应，合成了１２个含或不含手性碳的大位阻取代茂金属有机化合物，并研究了它们的１ＨＮＭＲ，ＥＩＭＳ和ＩＲ．     

2-氰基-3-甲硫基-3-取代甲氨基丙烯酸酯类化合物的合成及其除草活性

A series of 2-cyano-3-methylthio-3-substituted methylaminoacrylates were synthesized as herbicidal inhibitors of photosystem Ⅱ （PSⅡ） electron transport, in order to estimate the effect of fluorine atom, pyridyl group, chirality and ester chain on activity. The important intermediate 2-fluoro-5-aminomethylpyridine was synthesized with high yield. The bioassay results showed that most of rifle compounds had high herbicidal activity in postemergence treatment. The introduction of an a-methyl into the 3-substituted methylamino could improve the activity notably. The replacement of hydrogen by chlorine or fluorine group and phenyl by pyridyl group showed different effects, and at the same time, the ester chain affected the activity too.     

Reaction of the carbonate radical with substituted anilines

Rate constants for the reaction of carbonate radical with aniline and some parasubstituted anilines have been determined by the flash photolysis technique. Using σ⁺ para values the rate constants at pH 8.5 correlate very well with the Hammett equation yielding ρ= − 1. The carbonate radical oxidises aniline giving the anilino radical. The products so formed have been identified through studies under conditions of continuous irradiation.     

Dynamic Lie algebraic formulation of second‐order optical nonlinearity for substituted benzenes

A dynamic Lie algebraic (DLA) formulation is applied to the study of nonlinear optical properties of the substituted benzenes. We have described the generation of the dynamic Lie algebra for the model Hamiltonian used in the present study. In terms of these elements of the dynamic algebra we express the evolution operator as a function of the group parameters, which can be determined by means of solving a system of coupled nonlinear differential equations. Thus, in terms of the density matrix operator formalism in statistical mechanics we obtain the statistical averages of the electric polarization and then derive readily an expression for the hyperpolarizability of the paradisubstituted benzenes. Comparisons with experimental observations and other quantum calculations of the hyperpolarizabilities for the paradisubstituted benzenes are made qualitatively and quantitatively. These results imply that the DLA method appears useful in describing the nonlinear optical phenomena in the substituted benzene molecules. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem 93: 335–343, 2003     

β—型过渡元素三取代钨锗杂多配合物的合成,表征和催化活性

报道Ａ－β－Ｍ＇ｘＨｙ－［ＧｅＷＯＭ３（Ｈ２Ｏ）３Ｏ３７］．ｎＨ２Ｏ（Ｍ＝Ｃｒ＾３＾＋，Ｃｏ＾２＾＋，Ｎｉ＾２＾＋，Ｃｕ＾２＾＋；Ｍ＇＝Ｂｕ４Ｎ＾＋，Ｋ＾＋）的立体有择合成法制备及红外和远红外光谱，紫外和可见光谱和循环伏安，磁化率和磁矩，ＸＰＳ，ＥＳＲ以及催化活性等研究结果。     

Synthesis of substituted polymethylenes by radical polymerization of N,N,N′,N′-tetraalkylfumaramides and their characterization

Radical polymerization of N,N,N′,N′-tetraalkylfumaramides (TRFAm) bearing methyl, ethyl, n-propyl, isopropyl, and isobutyl groups as N-substituents (TMFAm, TEFAm, TnPFAm, TIPFAm, and TIBFAm, respectively) was investigated. In the polymerization of TEFAm initiated with 1,1′-azobiscyclohexane-1-carbonitrile (ACN) in benzene, the polymerization rate (R_p) was expressed as follows: R_p = k [ACN]^0.28 [TEFAm]^1.26, and the overall activation energy was 102.1 kJ/mol. The introduction of a bulky alkyl group into N-substituent of TRFAm decreased the R_p in the following order: TMFAm > TEFAm > TnPFAm > TIBFAm > TIPFAm ～ 0. The relative reactivities of these monomers were also investigated in radical copolymerization with styrene (St) and methyl methacrylate (MMA). In copolymerization of TRFAm (M₂) with St (M₁), monomer reactivity ratios were determined to be r₁ = 1.07 and r₂ = 0.20 for St–TMFAm, and r₁ = 1.88 and r₂ = 0.11 for St–TEFAm, from which Q₂ and e₂ values were estimated to be 0.35 and 0.44 for TMFAm, and 0.19 and 0.47 for TEFAm, respectively. The other TRFAm were also copolymerized with St, but copolymerization with MMA gave polymers containing a small amount of TRFAm units. The polymer from TRFAm consists of a less-flexible poly(N,N-dialkylaminocarbonylmethylene) structure. The solubility and thermal property of the polymers were also investigated.     

15N NMR spectral parameters of compounds of the N-methylpyrazole series

The¹⁵N NMR chemical shifts and¹⁵N-¹H SSCCs are presented for substituted N-methylpyrazoles with substituents such as CH₃, NO₂, Br, Cl, NH₂, O=CNH₂, O=CPh, and COOH at the carbon atoms. The¹⁵N chemical shifts of the cyclic atoms of nitrogen and the nitro groups are discussed as well as the geminal and vicinal SSCCs of the ring nitrogen atoms with the hydrogen atoms of the CH and CH₃ fragments.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117334 Moscow. D. I. Mendeleev Chemico-Technological Institute, Moscow, Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2554–2561, November, 1992.     

Stereochemistry of [4 + 2] Cycloadditions of Perfluorinated Selenocarbonyls to 1, 3‐Dienes

In completely stereospecific [4+2] cycloadditions, the perfluorinated selenocarbonyls 1 and 2 react both with trans‐trans‐2, 4‐hexadiene and cis‐trans‐2, 4‐hexadiene to yield 3, 6‐dihydro‐cis‐3, 6‐dimethyl‐2H‐selenapyrans 3 , 4a and 4b . The observed stereoselectivity leads to the conclusion, that the [4+2] cycloaddition of perfluorinated selenocarbonyls follows a concerted pathway. An identical mixture of isomers was isolated when using the precursor for 2 , trimethylstannyl (pentafluoroethyl)selane, which reacts with both 1, 3‐dienes over several weeks to form a mixture of syn‐2‐fluoro‐3, 6‐dihydro‐cis‐3, 6‐dimethyl‐2‐trifluoromethyl‐2H‐selenapyran ( 4a ) and anti‐2‐fluoro‐3, 6‐dihydro‐cis‐3, 6‐dimethyl‐2‐trifluoromethyl‐2H‐selenapyran ( 4b ) in the same ratio as found for 2 , thus proving the intermediate formation of Se=C(F)CF₃ ( 2 ). Complex 2D NMR experiments were used to distinguish the isomers 4a and 4b and to assign the ¹H, ¹³C and ¹⁹F NMR data of the selenaheterocycles.     

取代基物化参数及其在药物定量构效关系中的应用

把取代基电性、立体及疏水性物化参数组合建立一种新取代基描述方法, 对环尿素类和N,N-二甲基-2-溴苯乙胺类衍生物进行结构表征. 对训练样本集通过逐步回归筛选变量, 所建多元线性回归方程R2分别为0.853和0.960, 留一法交互检验Rcv2分别为0.723和0.901；用预测集样本作外部预测, 所得Qext2分别为0.7617和0.7653. 结果显示：环尿素类化合物结构中苯环邻位立体、间位疏水、对位疏水及立体因素对该类药物抗HIV活性产生阻抑作用； N,N-二甲基-2-溴苯乙胺类苯环上取代基立体因素及对位给电子效应有利于提高肾上腺素能阻断活性.     

Synthesis and Characterization of Ethylthioethylcyclopenta-dienyl Organolanthanide Complexes:Cp_2~(Th)LnCl(Ln=Gd,Dy),Cp_2LnCp~(Th)(Ln=Yb,Sm,Dy,Y) and Cp~(Th)ErCl_2·2THF

Introduction Functional substituted cyclopentadienyl organolan-thanide complexes continue to attract considerable at-tention because these donor-functionalized side chains can increase the stability of highly reactive organolan-thanide complexes by forming the additional in-tramolecular chelating coordination with the central metal, and for early lanthanide complexes, the enhanced stability offers the opportunity to explore the reactivity of the remaining ligands.1-4 In addition, the in-tramol…