Ruthenium‐catalyzed formal alkyl group transfer: Synthesis of quinolines from nitroarenes and alkylammonium halides

Nitroarenes are reductively cyclized with an array of tetraalkylammonium halides and trialkylarnmonium chlorides in the presence of a catalytic amount of a ruthenium catalyst along with tin(II) chloride dihydrate at 180° to afford the corresponding quinolines in moderate to good yields. The addition of tin(II) chloride dihydrate is necessary for the effective formation of quinolines and toluene is the solvent of choice. A reaction pathway involving initial reduction of nitroarenes to anilines and conversion of alkylammonium halides to alkylamines, alkyl group transfer from alkylamines to anilines to form an imine, dimerization of imine, and heteroannulation is proposed for this catalytic process.     

β-内酰胺类抗生素酶促合成新进展

β-内酰胺类抗生素的合成在制药工业中占据重要的地位, 相关的酶促合成方法研究备受关注; 酶促合成显著提高合成效率, 减少三废的排放, 是实现绿色合成的有效方法. 综述了近年来β-内酰胺类抗生素酶促合成研究的新进展, 包括一锅合成法、原位产物排出法、介质技术和酶固定化方法.     

铁氰化钾-鲁米诺体系后化学发光反应及其分析应用研究 ————-分子印迹-后化学发光法测定双嘧达莫

研究了双嘧达莫在铁氰化钾-鲁米诺化学发光反应体系中的后化学发光反应, 并在研究其反应的动力学性质、化学发光光谱、荧光光谱以及一些相关问题的基础上, 探讨了反应机理; 合成了双嘧达莫的分子印迹聚合物, 以此聚合物为分子识别物质, 利用铁氰化钾-鲁米诺-双嘧达莫后化学发光体系, 建立了测定双嘧达莫的高选择性分子印迹-后化学发光分析方法. 所建方法的线性范围为1.0×10-8-1.0×10-6 g/mL(r=0.999 2), 检出限为3×10-9 g/mL, 相对标准偏差为2.7%(1.0×10-7 g/mL双嘧达莫, n=11).     

尖晶石型LiMn2O4电池材料的元素掺杂

尖晶石型LiMn2O4正极材料因资源丰富、无毒、安全及制备简单、技术较成熟等优点而成为最具竞争力的新一代商用锂离子二次电池的正极材料之一.由于LiMn2O4的循环稳定性、高温(＞55℃)稳定性和大电流放电等因素限制了推广应用.本文从材料的结构组成对锂离子嵌脱过程的作用机理,论述了元素掺杂对尖晶石型LiMn2O4正极材料电化学特性的影响,指出了元素掺杂本体改性锰酸锂正极材料的方法和特点.     

Optically active sum frequency generation from molecules with a chiral center: amino acids as model systems

With amino acids as model systems, optically active sum frequency generation (OA-SFG) was used to probe the chirality of molecules with a chiral center and an intrinsically achiral chromophore in isotropic solution for the first time. Like that of circular dichroism (CD), the OA-SFG's near electronic resonance originates from the extrachromophoric chiral perturbation on the carboxyl chromophore. The difference in the relative strengths of OA-SFG and CD among different amino acids can be explained by the difference in the details of perturbations.     

Adenanthusone,a New Ursane Type Nortriterpenoid from Isodon adenanthus

A new ursane‐type nortriterpenoid, adenanthusone (=(11α,12α)‐4‐demethyl‐11,12‐epoxy‐3,13‐dihydroxy‐2‐oxoursa‐3,20(30)‐diene‐28‐oic acid γ‐lactone; 1 ) was isolated from Isodon adenanthus. Its structure was determined by NMR spectra and X‐ray crystallographic diffraction analysis. The biogenetic implication of the nortriterpene is discussed.     

基于三维静电势参数研究C60溶解性的构效关系

在量子化学从头算基础上,对一系列溶剂化合物分子进行了结构优化和三维静电势参数计算,运用多元线性回归分析和神经网络方法对C60在121种不同溶剂的溶解性与计算的结构参数进行了构效关系研究.用建立起来的QSPR 关系式对15种不同结构类型溶剂进行了预测,并阐述了C60溶质与不同溶剂之间的相互作用,获得了满意的结果.     

Determination of proteins with Alizarin Red S by Rayleigh light scattering technique

A new protein determination method by enhanced Rayleigh light scattering (RLS) technique has been developed. In acid condition (pH=3.60), RLS of 1,2-dihydroxyanthraquinone-3-sulfonate (Alizarin Red S) can be greatly enhanced by addition of proteins, resulting in two characteristic peaks, 360 and 505 nm, respectively. The new protein assay is based on the RLS enhancement and spectrum change. The optimum condition for the reaction was investigated. The linear range is 0.20-24.9 μg ml⁻¹ for BSA and 0.20-15.5 μg ml⁻¹ for HSA. The detection limits (S/N=3) are 9.59 ng ml⁻¹ for BSA and 9.51 ng ml⁻¹ for HSA. The results of determination for human serum samples were comparable to those obtained by Bradford method. The binding stoichiometry was determined.     

A New Activation Method for Electroless Metal Plating：Palladium Laden via Bonding with Self—Assembly Monolayers

A new activation method has been developed for electroless copper plating on silicon wafer based on palladium chemisorption on SAMs of APTS without SnCl2 sensitization and roughening condition.A closely packed electroless copper film with strong adhesion is successfully formed by AFM observation.XPS study indicates that palladium chemisorption occurred via palladium chloride bonding to the pendant amino group of the SAMs.