[Cu(Ⅱ)(DETA)]3[Cr(CN)6]2·5H2O(DETA=二乙烯三胺) 氰桥配合物的结构和磁性研究

近十几年来,以氰根为配体的双过渡金属配合物在分子磁、微电子领域的研究呈现出广泛的应用前景[1～4],该领域已成为各国科学家关注的焦点.其中普鲁士蓝类双过渡金属配合物是分子磁领域的一个重要分支[5～8],在已发现的这个系列配合物中有的其相转变温度Tc值高达376 K[9].     

利用热分析质谱联用技术(TA-MS)分析比较配合物及双配合物的热分解行为——介绍一个综合性研究型化学实验

应用热分析．质谱联用技术考察了反式-[Co（en）2Cl2]Cl、K3[Fe（C2O4）3]·3H2O配合物以及相应的双配合物——反式-[Co（en）2Cl2]3[Fe（C2O4）3]·4．5H2O的程序升温热分解行为。通过对样品的热失重分析、逸出气体的质谱分析以及固相产物的物相分析,了解其热分解过程机理,比较了在受热过程中反式-[Co（en）2Cl2]Cl、K3[Fe（C2O4）3]·3H2O配合物和双配合物的过渡金属离子与配体之间以及配体与配体之间的相互作用的变化。     

稀土-过渡金属桥联异四核配合物的磁性及电化学研究

合成了两种不对称草酰胺桥联异四核配合物[Cu(oxca)]3M(H2O)2·5H2O[oxca表示N (2 羧基苯)·N′ (3 氨丙基)草酰胺三价阴离子,M=Nd(Ⅲ),Gd(Ⅲ)]。用元素分析、红外光谱、电子光谱等对所合成配合物进行了表征。在DMSO中采用循环伏安法研究了配合物的电化学性质。在4～300K范围内测量了[Cu(oxca)]3Gd(H2O)2·5H2O体系的变温磁化率,经拟合得磁参数J=0.537cm-1。结果表明异四核配合物分子内金属离子间存在较弱的铁磁性自旋交换相互作用。     

氰根桥联大环配合物的合成、结构与磁性研究

合成了三个氰根桥联的十二核大环齿轮状配合物[Cr（bpmb）（CN）2]6-[Mn（5-Brsalpn）]6·12H2O（1）、[Co（bpmb）（CN）2]6[Mn（5-Brsalpn）]6·12H20（2）和[Co（bpmb）-（CN）2]6[Mn（5-Clsalpn）]6·24H20·8CH3CN（3）（bpmb^2-=1,2-bis（pyridine·2-carboxamido）-4-methylbenzenate）,表征了其晶体结构和磁性．三配合物是同晶型的,包含交替排列的锰（Ⅲ）-Schiff碱阳离子和[M（bpmb）（CN）2]-阴离子,阴阳离子单元用氰根离子连成十二核环状结构．分子环直径约2nm．配合物1呈反铁磁性,说明通过氰根桥铬（Ⅲ）．锰（Ⅲ）离子间存在反铁磁相互作用．基于一维交替链模型（哈密顿算符H=-JCrMnN∑i=0Si·Si＋1）导出的磁化率公式与实验数据进行拟和得到磁耦合参数JCrMn=-2．65（6）cm^-1．     

固相配位化学反应研究 XXIII: 一取代基五氰合铁(II)类配合物热分解反应的研究

本文以气相色谱法为主要手段, 配合Mossbauer谱、红外光谱等结构分析方法, 研究了一系列一取代基五氰合铁(II)类配合物Na2[Fe(CN)5L]·mH2O及Na3[Fe(CN)5L']·nH2O(L=NO^+、N2H5^+、enH^+, L'=NH3、H2O、Py)的热分解反应。结果表明所有一取代五氰合铁(II)配合物热分解过程中都形成相同的中间化合物Na4[Fe(CN)6]和Fe2[Fe(CN)6], 各配合物热分解放出取代基L(L')的温度次序与L(L')在光谱化学序列中的次序一致。本文以亚硝基铁氰化钠为代表, 详细讨论了该系列配合物的热分解反应机理以及热稳定性的规律性。     

新型一维链状氰根桥联配合物[Eu(DMF)4(H2O)2Mn(CN)6*H2O]n的合成与晶体结构

以K3Mn(CN) 6,N ,N 二甲基甲酰胺和Eu(NO3) 3·6H2 O为原料合成了新型一维链状氰根桥联配合物[Eu(DMF) 4(H2 O) 2 Mn(CN) 6·H2 O]n,并通过元素分析、红外光谱和紫外光谱进行了表征 .利用单晶X射线四圆衍射测定了配合物的晶体结构 ,结果表明 ,晶体属单斜晶系 ,P2 1/c空间群 ,晶胞参数a =1.2 992 (3)nm ,b =1.2 76 4(3)nm ,c =1.915 4(4 )nm ,β =10 9.42 (3)°,V =2 .995 6 (12 )nm3,Dx=1.5 73Mg/m3,Z =4,R =0 .0 372 ,Rw=0 .0 96 2 ,GOF =1.0 95 .在Eu和Mn原子之间存在两个CN桥 ,配合物呈现一维链状结构 .     

固相配位化学反应研究 XXIII: 一取代基五氰合铁(II)类配合物热分解反应的研究

本文以气相色谱法为主要手段, 配合Mossbauer谱、红外光谱等结构分析方法, 研究了一系列一取代基五氰合铁(II)类配合物Na2[Fe(CN)5L]·mH2O及Na3[Fe(CN)5L']·nH2O(L=NO^+、N2H5^+、enH^+, L'=NH3、H2O、Py)的热分解反应。结果表明所有一取代五氰合铁(II)配合物热分解过程中都形成相同的中间化合物Na4[Fe(CN)6]和Fe2[Fe(CN)6], 各配合物热分解放出取代基L(L')的温度次序与L(L')在光谱化学序列中的次序一致。本文以亚硝基铁氰化钠为代表, 详细讨论了该系列配合物的热分解反应机理以及热稳定性的规律性。     

对二茂铁基苯甲醛双缩间苯二胺盐酸盐Schiff碱及其过渡金属配合物的合成与表征

合成了新的二茂铁基苯甲醛双缩间苯二胺盐酸盐Schiff碱[m-C6H4(NCH)2(Cp′FeCp)2]及其过渡金属配合物[m-C6H4(NCH)2(Cp′FeCp)2·MCl2(M=Pd2+,Fe2+,Zn2+)]。其结构经1HNMR,IR和元素分析表征。     

钨磷杂多酸盐的合成、表征及催化活性

合成了4个钨磷杂多酸盐——K10H2[P2W15Ti3O62]·2H2O,K12[P2W15(TiO2)3O59]·8H2O,K12[P2W15Zr3O62]·6H2O和K12[P2W15(ZrO2)3O59]·5H2O,用183WNMR,UV,IR,ICP和极谱-循环伏安等测试方法对其性质、结构进行了研究。结果表明它们都是具有Dawson结构的杂多配合物,对顺丁烯二酸的H2O2环氧化反应具有显著的催化活性。     

过渡金属二取代三元杂多酸盐的制备和表征

在水中由Na2 WO4 ·2H2 O ,Na2 MoO4 ·2H2 O和KH2 PO4 ·2H2 O反应生成具有半Dawson结构的钨钼混配杂多阴离子Na9PW6Mo3O34 ·1 0H2 O。以阴离子和过渡金属硝酸盐为原料在水溶液中合成了一系列过渡金属二取代的具有Keggin结构的杂多酸四丁基铵盐 [TBA]4 Hn[PW7Mo3M2 O38(H2 O) 2 ]·C3H6O(n =1 ,M =Fe3+;n =3,M =Mn2 +,Co2 +,Ni2 +,Cu2 +) ,用元素分析和波谱进行了表征。     

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.     

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.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.     

Copper-catalyzed multicomponent reactions of 2-iodoanilines,benzylamines, and elemental sulfur toward 2-arylbenzothiazoles

A relatively cheap copper salt-catalyzed, three-component approach providing 2-arylbenzothiazoles in good to excellent yields from readily available 2-iodoanilines, benzylamines, and sulfur powder is reported. This methodology allows preparation of various classes of 2-arylbenzothiazoles and provides a general, reliable approach.