基于2-(4'-羧基苯基)咪唑-4,5-二羧酸构筑的三个镉/锌配位聚合物的合成、拓扑结构、荧光光谱及DNA作用

以2-（4''-羧基苯基）咪唑-4,5-二羧酸（H₄CPhIDC,C₁₂H₈N₂O₆）为配体,用溶剂热合成了3种配位聚合物{[Cd₂（CPhIDC）（bimb）]·H₂O}_n（1）、{[Cd₂（CPhIDC）（phen）₂]·3H₂O}_n（2）、{[Zn₂（CPhIDC）（bpp）]·1.5H₂O}_n（3）（bimp=1,4-双咪唑基-丁烷,phen=1,10-菲咯啉,bpp=1,3-双（4-吡啶基）-丙烷）。用元素分析、红外光谱、粉末X射线衍射和单晶X射线衍射对配合物进行了表征和结构分析。结构分析表明,主配体以完全去质子化CPhIDC^4-的形式与中心金属离子形成以μ₄和μ₅为配位模式的二维及三维聚合物。配合物1和3是三维网络结构,同时呈现（3,4,5）-连接的（5·6·7）（4·5²·6·7²）（4·5²·6·7⁴·8²）拓扑结构,两者的不同之处是中心离子和辅助配体。配合物2是二维波纹状渔网结构,呈现4⁴·6²拓扑结构,在其空间填充上又类似于DNA双螺旋链的单螺旋结构。测定了产物的固体荧光光谱;用EtBr荧光探针法研究了配体及配合物与ct-DNA的相互作用。     

2，6-二乙酰吡啶缩水杨酰腙衍生物的锰和镧配合物的合成、晶体结构及抗肿瘤活性

设计并合成了2,6-二乙酰吡啶缩水杨酰腙衍生物（2,6-（（o-OH） C₆H₄C=ONHN=C （CH₃））₂C₅H₃N,H₄L）及其锰配合物[Mn （H₂L）（DMSO）₂]（1）和镧配位聚合物{[La （H₂L）₂]₂[La₂（H₂L）₂（DMF）₅（H₂O）]·2DMF·2H₂O}_n（2）（DMSO=二甲基亚砜,DMF=N,N-二甲基甲酰胺）。配合物1和2的结构分别通过红外光谱、紫外可见光谱、元素分析进行了表征,并经单晶X射线衍射进一步确证。晶体结构分析表明配合物1属于正交晶系的P2₁2₁2₁空间群;配位聚合物2结晶于三斜晶系的P1空间群。用CCK-8法检测了1和2对体外结肠癌细胞HCT116和结直肠腺癌上皮细胞DLD-1的增殖抑制作用,结果表明1和2对HCT116和DLD-1细胞都有中等抑制作用：1的IC₅₀分别为（23.69±1.226）μmol·L^-1和（41.06±1.013）μmol·L^-1;2的IC₅₀分别为（57.61±1.034）μmol·L^-1和（61.36±1.029）μmol·L^-1。     

两个Gd2配合物的晶体结构及磁制冷性质

使用多齿席夫碱配体（H₂L=pyridine-2-carboxylic acid （3,5-di-tert-butyl-2-hydroxy-benzylidene）-hydrazide）分别与Gd （dbm）₃·2H₂O （Hdbm=二苯甲酰基甲烷）及Gd （NO）₃·6H₂O反应,通过溶剂热法得到了2个新的Gd₂配合物[Gd₂（L）₂（dbm）₂（C₂H₅OH）₂]（1）和[Gd₂（L）₂（HL）₂（DMF）]·2CH₃CN （2）（DMF=N,N-二甲基甲酰胺）,并对其结构与磁性质进行了系统的研究。单晶结构分析表明配合物1中的每个中心Gd(Ⅲ)离子均为8配位,其配位几何构型为略微变形的三角十二面体,相邻的中心Gd(Ⅲ)离子通过2个μ₂-O连接形成了平行四边形的Gd₂O₂核心;配合物2中的每个中心Gd(Ⅲ)离子均为9配位,其配位几何构型为扭曲的球形单帽四方反棱柱,相邻的中心Gd(Ⅲ)离子通过3个μ₂-O连接形成了三角双锥形的Gd₂O₃核心。磁性测试表明配合物1和2具有磁制冷性质,其最大磁熵变（-ΔS_m）分别为20.16 J·K^-1·kg^-1（T=2.0 K,ΔH=70 kOe）和17.14 J·K^-1·kg^-1（T=2.0 K,ΔH=70 kOe）。     

一种镉基配位聚合物的合成及其对2，4，6-三硝基苯酚的荧光识别

以1,3-金刚烷二甲酸（H₂adc）和3,6-二（4-吡啶基）-9-（4-吡啶苯基）-9H-咔唑（dppc）为配体,通过溶剂热法构筑了一个新型的Cd（Ⅱ）基配位聚合物：{[Cd（adc）（dppc）（H₂O）]·2H₂}_n （1）。配合物1属于单斜晶系,C2/c空间群,具有二维层状结构,相邻的层与层之间通过氢键等弱相互作用形成一个三维超分子结构。1具有良好的荧光性,能够对DMF溶液中的2,4,6-三硝基苯酚实现高灵敏、高选择的荧光猝灭检测,其K_sv可达7.6×10⁴ L·mol^-1。     

一例基于5-((萘-1-基甲基)氨基)间苯二甲酸配体的Cd（Ⅱ）金属有机骨架的合成、晶体结构及对酸性氨基酸的检测

以5-（（萘-1-基甲基）氨基）间苯二甲酸（H₂L）与Cd²⁺通过溶剂热法合成出二维层状金属有机骨架[Cd （L）（H₂O）]·H₂O （1）。结构分析显示层与层之间通过π-π和C—H…π相互作用形成了三维超分子结构。值得注意的是,1在酸性条件下发光会显著增强,这可用于选择性的检测酸性氨基酸,1对天冬氨酸和谷氨酸的检测限分别为3.88和5.43 μmol·L^-1。     

基于柔性四羧酸配体构筑的两个镉(Ⅱ)配位聚合物的晶体结构及荧光性质

通过溶剂热和水热合成的方法制备了2个Cd（Ⅱ）配位聚合物[Cd₂（L）（DMF）_1.5（H₂O）₂]_n（1）和{[Cd（L）_0.5（4,4''-bpy）（H₂O）]·2H₂O}_n（2）（H₄L=5,5''-（己烷-1,6）-双-（氧基）-二-间苯二甲酸）。结构分析表明配合物1是一个（4,4）-连接的sql拓扑网络,拓扑符号为{4⁴·6²}₂。配合物2是一个（4,4,4）-连接的三重穿插的bbf网络,拓扑符号为（6⁶）（6⁴·8²）。配合物1和2都呈现出较好的热稳定性和荧光性质。     

基于柔性四羧酸配体构筑的两个镉(Ⅱ)配位聚合物的晶体结构及荧光性质

通过溶剂热和水热合成的方法制备了2个Cd（Ⅱ）配位聚合物[Cd₂（L）（DMF）_1.5（H₂O）₂]_n（1）和{[Cd（L）_0.5（4,4''-bpy）（H₂O）]·2H₂O}_n（2）（H₄ L=5,5''-（己烷-1,6）-双-（氧基）-二-间苯二甲酸）。结构分析表明配合物1是一个（4,4）-连接的sql拓扑网络,拓扑符号为{4⁴·6²}₂。配合物2是一个（4,4,4）-连接的三重穿插的bbf网络,拓扑符号为（6⁶）（6⁴·8²）。配合物1和2都呈现出较好的热稳定性和荧光性质。     

两个基于Cd(Ⅱ)金属有机骨架化合物在金属离子和有机分子发光传感中的应用

合成了2个镉（Ⅱ）金属有机骨架化合物{[Cd（L）（fma）]·0.5H₂O}_n（1）和{[Cd（L）_0.5（sdb）]·DMF}_n（2）（L=E,E-2,5-二己氧基-1,4-双（2-乙烯-吡啶基）苯,H₂fma=延胡酸,H₂sdb=4,4''-磺酰基二苯甲酸）,研究了它们在金属离子和有机分子的发光传感中的应用。结果表明,Fe³⁺对配位聚合物1和2的发光强度有明显的猝灭作用。此外,聚合物1和2还对水杨醛具有明显的猝灭能力。     

基于三唑配体的金属锰（Ⅱ）、锌（Ⅱ）配合物的合成、晶体结构与性质研究

在不同反应条件下,采用三唑衍生物作为配体与乙酸锰和硝酸锌反应,合成了2个具有三维结构的配位化合物{Mn（pytyba）（H₂O）₃]·2H₂O}_n（1）和{[Zn（pytyba）（H₂O）₃]·4H₂O}_n（2）,并通过元素分析、热重分析、荧光性、X射线单晶衍射对化合物进行分析。结构分析表明1和2有许多共同特征：两个聚合物的晶体均属于单斜晶系,C2/c空间群,Mn²⁺和Zn²⁺均为六配位畸变八面体配位结构,具有相似的热稳定性、荧光性以及相近的孔隙率。配体中的氧原子与金属离子配位形成一维链状结构,然后又通过O-H…N、O-H…O氢键作用和π…π芳香堆积形成超分子结构。此外,通过测定化合物抗氧化活性（SOD）的经典方法-Marklund法对配合物1和2的抗氧化活性进行了研究。     

基于柔性双吡啶双酰胺和两种不同多羧酸配体的三个Cu（Ⅱ）/Co（Ⅱ）配位聚合物：组装、结构和性质

通过水热合成得到3个有机金属配位聚合物,即[Cu（1,2-BDC）（L）]（1）,[Cu（HBTC）（L）]·2H₂O（2）,[Co（HBTC）（L）]·H₂O（3）,（L=N,N-双（3-氨基吡啶）乙二酰胺,1,2-H₂BDC=1,2-邻苯二甲酸和H₃BTC=1,3,5-均苯三甲酸）。配合物1是基于1D[Cu-1,2-BDC]_n和[Cu-L]_n链形成的一个3DCdSO₄-型拓扑结构。配合物2~3是同构的,均显示出2D双层（3,5）-连接的{4²·6⁷·8}{4²·6}拓扑结构。相邻的2D双层网络通过分子间的氢键（配合物2）和π-π堆积（配合物3）作用进一步拓展成3D超分子框架。我们对芳香羧酸和中心金属离子对配合物结构的影响进行了详细的讨论。此外,还研究了配合物1~3的电化学性质和固态荧光性质。     

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.     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

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.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.