蒽镁的某些化学反应

本文报道了蒽镁与O_2,H_2,C_2H_2,CO,CO_2,(CH_3)_2CO,C_2H_5Br的反应。其中,蒽镁与(CH_3)_2CO和C_2H_5Br的反应可以分别作为合成(9,10-二氢-9-蒽基)二甲基甲醇和9,10-二乙基-9,10-二氢蒽的简易方法。     

Ortho-Hydroxylation of Phenol by Tyrosinase Model Compounds

A series of tyrosinase model ligands and complexes containing polyimidazoles were prepared. 2, 4-Di-tert-butyl-phenol was ortho-hydroxylated by the binuclear copper (I) complex [Cu2(6a)(CH3CN)2](ClO4)2 8a and molecular dioxygen under mild conditions with up to 80.4% yield, 91.4% selectivity and 92.0% conversion.     

ArCCo~3(CO)~9~-~nL~n的化学ETC合成及其电化学研究

利用由化学还原剂BPK引发的电子迁移催化反应(ETC)合成了两个系列八种新的三核钴簇合物p-RC~6H~4CCo~3(CO)~9~-~nL~n(L=PPh~3, n=1; L=P(OEt)~3, n=2)。用m.p.、元素分析、IR及^1H NMR对簇合物进行了表征。对簇合物在Pt电极上的循环伏安(CV)研究表明, p-RC~6H~4CCo~3(CO)~9及PPh~3单取代物在室温下均经历一个可逆的单电子过程。p-RC~6H~4CCo~3(CO)~9的E~1~/~2与R的σ~m线性关系表明R通过诱导效应影响簇合物的氧化还原性。取代簇合物的还原电势相对于母体簇合物的负转移表明P的配位增大了CCo~3上的电荷密度, 导致簇合物难被还原。     

一种经(E)-α-碘代烯基砜的钯催化交叉偶联反应立体选择合成(1Z,3E)-2-芳砜基取代的1,3-二烯的新方法

（E）-α-Stannylvinyl phenyl（or p-tolyl）sulfones underwent an iododestannylation reaction to afford （E）-α-iodovinyl phenyl（or p-tolyl）sulfones 1, which reacted with （E）-alkenylzirconium（IV） complexes 2 produced in situ by hydrozirconation of terminal alkynes in the presence of a Pd（PPh3）4 catalyst to afford stereoselectively （1Z,3E）-2- phenyl（or p-tolyl）sulfonyl-substituted 1,3-dienes 3 in good yields.     

Development and Validation of Spectrophotometric Methods for the Determination of Cefetamet in Pharmaceutical Dosage Forms

Two simple and sensitive spectrophotometric methods for the determination of cefetamet in either pure form or in its pharmaceutical formulations were described. The method Ⅰ is based on the interaction of 3-methylbenzo[d]- thiazolin-2-one hydrazone （MBTH） with cefetamet in the presence of freshly prepared ferric chloride in a neutral medium. The resulting blue colored product has λmax at 628 nm. The method Ⅱ describes the reduction of ferric ion by the drug to ferrous ion followed by a complex formation reaction with 1,10-phenanthroline （1,10-phen） to form an orange red colored chromogen exhibiting 2max at 510 nm. The products are stable for more than 5 and 8 h respectively. Common excipients used as additives in pharmaceutical preparations do not interfere in the proposed methods. Both methods are highly reproducible and have been applied to a wide variety of pharmaceutical preparations and the results are comparable with those of official methods.     

十六烷基胺稳定的CdSe纳米晶体的合成与表征

用CdO通过高温化学方法制备了具有高发光特性的CdSe胶体纳米晶.通过改变配体十六烷基胺在反应体系中的含量,合成了3种不同粒径的CdSe纳米晶.利用TEM、XRD和光谱等手段对合成出来的CdSe纳米晶的形貌结构和发光特性进行了表征.结果表明,随着十六烷基胺在反应体系中量的增多,CdSe纳米晶的粒径增大.通过调整十六烷基胺在反应体系中的量可以方便地控制纳米晶的尺寸.     

11,12,13-三甲基-1,4,7,10-四氮杂十三环-10,13-二烯-镍(Ⅱ)配合物催化的新型振荡化学反应

本文报道了一种新型振荡化学反应体系—BrO_3~--MA-H_2SO_4-[Ni(L-H)]X(X为配阴离子)体系,其中MA为丙二酸,L代表题给大环11,12,13-三甲基-1,4,7,10-四氮杂十三环-10,13-二烯.测得了该体系发生振荡的组分浓度范围;研究了各物种浓度、自由基抑制剂和还原剂对振荡反应的影响;还测得了振荡的轨迹为螺旋线而非极限环,由于催化剂消耗振荡衰减;初步提出了振荡反应发生的可能机理.     

LiF-Ni纳米复合薄膜的电化学性能研究

采用脉冲激光沉积法在不锈钢基片上制备了LiF-Ni纳米复合薄膜, 用充放电和循环伏安实验测量了该薄膜的电化学性能. 首次充电容量为107 mAh•g−1, 它对应第一次释放锂的过程. 在充放电循环过程中, 锂的嵌入、脱出通过非原位高分辨电子显微和选区电子衍射得到证实. 这一结果为LiF可以由过渡金属Ni驱动分解提供了直接的实验证据.     

掠射椭圆偏振谱学方法数理模型的研究

掠射椭圆偏振谱学方法通过现场测量椭圆偏振参量Δ和Ψ能够反映电极过程的性质及变化规律.将电化学反应中的扩散层模型与掠射椭圆偏振实验体系相结合,提出了掠射椭圆偏振谱学方法的数理模型,对掠射椭圆偏振参量Δ和Ψ的物理化学意义做出了解释,认为电极表面附近的溶液扩散层对于椭圆偏振光既有相位延迟器的作用,又有振幅吸收器的作用；并应用一些实验结果,分析了电解液中电活性物质浓度和入射光束斑直径对掠射椭圆偏振参量的影响.     

Hydrolysis Reaction of N-Phosphoryl-α-, β- and γ-amino Acids Studied by HPLC

The hydrolysis reactions of N-（O,O＇diisopropyl）phosphoryl-L-α-alanine （DIPP-L-α-Ala）, N-（O,O＇diisopropyl）- phosphoryl-D-α-alanine （DIPP-D-α-Ala）, N-（O,O＇-diisopropyl）phosphoryl-β-alanine （DIPP-β-Ala） and N-（O,O＇-diisopropyl）phosphoryl-γ-amino butyric acid （DIPP-γ-Aba）, were studied by HPLC and their hydrolysis reaction kinetic equations were obtained. Under acid conditions, the reaction rate of DIPP-L-α-Ala was close to that of DIPP-D-α-Ala and the same rule was true between DIPP-β-Ala and DIPP-γ-Aba. Meantime, the reaction rate of DIPP-L/D-α-Ala was as 10 times as that of DIPP-β-Ala or DIPP-γ-Aba. Under basic conditions, the hydrolysis reactions of DIPP-β-Ala and DIPP-γ-Aba almost did not take place and the reaction rate of DIPP-L/D-α-Ala was about 1/10 of that under acid conditions. Moreover, theoretical calculation further illuminated the differences of the hydrolysis rate from the view of energy. The results would provide some helpful clues to why nature chose a-amino acids but not other kinds of analogs as protein backbones.