萃取法研究Cu~（2＋）－bpy－PCA~－体系有机配体间的芳环堆积作用

萃取法研究Ｃｕ~（２＋）－ｂｐｙ－ＰＣＡ~－体系有机配体间的芳环堆积作用徐景华，龚钰秋，黄宪（杭州大学化学系杭州３１００２８）关键词芳环堆积作用，铜，联吡啶，苯基羧酸可用ｐＨ电位滴定、质子核磁共振、电子光谱和ＣＤ光谱、萃取等方法研究混配配合物配体间的芳...     

M（Ⅱ）（ATP）^2—与核酸碱基（腺嘌呤,胞嘧啶）三元混配配…

用ＰＨ电位滴定法测定 篱子（Ｍ＾２＋＝Ｃｕ＾２＋，Ｃｏ＾２＋，Ｎｉ＾２＝，Ｚｎ＾２＋，Ｃｄ＾２＋）与核酸碱基（Ｐ＝腺嘌呤，胞嘧啶）形成的二夫配合物以及与腺甘－５＇－三酸（ＡＴＰ）形成的三元混配配合物的稳定常数，三元配合物相对于二元酚物的稳定性用平衡常数ΔｌｇＫＭ大，这可能与三元混配配合物分子内存在配体间的芳环堆积、氢键作用以及πＡ－πＢ协同效应有关。     

M（Ⅱ）（ArP）~（2－）与核酸碱基（腺嘌呤，胞嘧啶）三元混配配合物稳定性研究

用ｐＨ电位滴定法测定了金属离子（Ｍ~（２＋）＝Ｃｕ~（２＋），Ｃｏ~（２＋），Ｎｉ~（２＋），Ｚｎ~（２＋），Ｃｄ~（２＋）与核酸碱基（Ｌ＝腺嘌呤，胞嘧啶）形成的二元配合物以及与腺昔－５’－三磷酸（ＡＴＰ）形成的三元混配配合物的稳定常数。三元配合物相对于二元配合物的稳定性用平衡常数表示。结果表明：ΔｌｇＫ_ｍ比咪唑或氨的相应配合物ΔｌｇＫ_ｍ大，这可能与三元混配配合物分子内存在配体间的芳环堆积、氢键作用以及π_Ａ－π_Ｂ协同效应有关。     

混配铂(Ⅱ)配合物堆积异构平衡的溶剂效应

在三元混配配合物中配体与配体之间的分子内芳环堆积是配体分子间的一种特殊作用形式 ,并且在溶液中存在着堆积异构平衡。这种由芳环堆积所产生的异构平衡也同样存在于生物体系内 ,并有着重要的生理效应[1 ,2 ] 。因而有关三元混配配合物分子内芳环堆积异构平衡的研究十分活跃[3～ 5] 。本文选定了羧酸系列配体 (ＣＡ)和另一配体 1 ,1 0 邻菲绕啉 (Ｐｈｅｎ)与铂 (Ⅱ)形成的三元混配配合物作为体系 ,系统研究了溶剂极性对三元混配配合物分子内芳环堆积异构平衡的影响。1　实验部分1 1　试剂和溶液标定氯铂酸钾 [Ｋ2 (ＰｔＣｌ4) ]、硝酸 (…     

配体分子结构对Pd(Ⅱ)-Phen-PCA体系堆积作用的影响

用pH电位滴定法测定了含l，10-邻菲咯啉(Phen)和羧酸(CA)配体的三元混配配合物Pd(Phen)(CA)体系的稳定常数，比较和讨论了各种三元混配配合物之间的稳定性差异．实验结果表明，在三元混配配合物Pd(Phen)(PCA)中(PCA为苯基羧酸)存在分子内芳环堆积作用，堆积程度依赖于苯基和配位的羧酸根之间的亚甲基数目，其中以2-苯乙酸和3-苯丙酸与邻菲咯啉为最佳堆积．     

1，10－双（1＇－苯基－3＇－甲基－5＇－氧代吡唑－4＇－基）癸二酮－［1，10］与1，10－菲罗啉或2，2＇－联吡啶对钴（Ⅱ）的协同萃取行为研究

本文研究了１，１０－双（１＇－苯基－３＇－甲基－５＇－氧代吡唑－４＇－基）癸二酮－［１，１０］（Ｈ２Ａ）与１，１０－菲罗啉（ｐｈｅｎ）或２，２＇－联吡啶（ｄｉｐｙ）对Ｃｏ（Ⅱ）的协同萃取行为．确定了协萃配合物的组成为ＣｏＡ·Ｂ（Ｂ分别为Ｐｈｅｎ和ｄｉｐｙ），求得萃取平衡常数ｌｏｇＫｅｘ分别是４．７８（Ｈ２Ａ＋ｐｈｅｎ）和１．６１（Ｈ２Ａ＋ｄｉｐｙ），并对协萃配合物的ＩＲ谱进行了讨论．     

Nd（CCl_3COO）_3（Phen）_2和［Eu（CCl_3COO）_2（P

Ｎｄ（ＣＣｌ_３ＣＯＯ）_３（Ｐｈｅｎ）_２和［Ｅｕ（ＣＣｌ_３ＣＯＯ）_２（Ｐｈｅｎ）_２２Ｈ_２Ｏ］~＋［ＣＣｌ_３ＣＯＯ］~－的电子结构和化学键成义祥，王培筠，陆维敏，董南（杭州大学化学系杭州３１００２８）关键词ＩＮＤＯ，稀土混配配合物，电子结构，化学键...     

铜(Ⅱ)与苯基羧酸(HPCA)和2,2''''-联吡啶衍生物(dpx)混配配合物的合成和表征

合成了铜（Ⅱ）与苯基羧酸根［ＰＣＡ－＝苯甲酸根（Ｂｚ－），２－苯乙酸根（ＰＡｃ－），３－苯丙酸根（ＰＰｒ－），４－苯丁酸根［ＰＢｕ－）］和２，２′－联吡啶衍生物（ｄｐｘ：２，２′－联吡啶胺ｄｐａ、２，２′－联吡啶酮ｄｐｋ、２，２′－联吡啶甲烷ｄｐｍ）三大系列１２种新的三元配合物。用元素分析、摩尔电导、红外光谱、１Ｈ核磁共振、差热分析等实验方法表征了它们的组成和性质。确定该系列配合物化学组成为Ｃｕ（ＰＣＡ）２（ｄｐａ）、Ｃｕ（ＰＣＡ）２（ｄｐｍ）、Ｃｕ（ＰＣＡ）２（ｄｐｋ）·ｎＨ２Ｏ（ｎ＝２－４）。它们具有相似的组成和配位方式。它们的可能结构为：二个ＰＣＡ－与Ｃｕ（Ⅱ）单齿配位，一个ｄｐｘ与Ｃｕ（Ⅱ）Ｎ，Ｎ二齿螯合配位。ｄｐｋ的羰基在金属离子Ｃｕ２＋的存在下发生水化作用成ｄｐｋ·Ｈ２Ｏ。用１ＨＮＭＲ法研究了Ｃｕ（Ｂｚ）２（ｄｐｘ）·ｎＨ２Ｏ和Ｃｕ（ＰＡｃ）２（ｄｐｘ）·ｎＨ２Ｏ二个体系其分子内或分子间可能存在的非共价键作用。     

镧系离子同乙酰水杨酸和1,10-二氮杂菲三元配合物的研究

合成了镧系离子（Ｌｎ＾３＋）同乙酰水杨酸（Ａｓａ）和１．１０－二氮杂菲（Ｐｈｅｎ）的三元配合物并确定其组成为Ｌｎ（ａｓａｌ）３·ｐｈｅｎ。考查了三元配合物的红外光谱、热稳定性和溶解性及其乙醇－水溶液的电子光谱和荧光光谱。     

镧系离子同乙酰水杨酸和1，10－二氮杂菲三元配合物的研究

合成了镧系离子（Ｌｎ３＋）同己酰水杨酸（Ａｓａｌ）和１．１０－二氮杂菲（Ｐｈｅｎ）的三元配合物并确定其组成为Ｌｎ（ａｓａｌ）３·ｐｈｅｎ．考查了三元配合物的红外光谱、热稳定性和溶解性及其乙醇－水溶液的电子光谱和荧光光谱．     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.