一类六核三价铁簇化合物的合成及结构表征

选择3种不同尺寸含氮配体（哌嗪、咪唑和三氮唑）与三羟甲基丙烷（H₃tmp）和FeCl₃采用溶剂热反应合成3例六核Fe（Ⅲ）合物：（C₅H₁₄N₂）[Fe₆（μ₆-O）Cl₆（tmp）₄]·2H₂O·CH₃OH （1）、（C₃H₅N₂）₂[Fe₆（μ₆-O）Cl₆（tmp）₄] （2）和（C₄H₈N₃）₃（C₂H₄N₃）[Fe12（μ₆-O）₂Cl₁₂（tmp）₈]·3CH₃OH （3）,并对它们的结构进行表征。发现三元醇配体有利于合成高核金属簇。3个化合物具有相同的阴离子簇[Fe₆（μ₆-O）Cl₆（tmp）₄]^2-。通过晶体学参数,元素分析,红外等手段证实,在化合物1和3的体系中,氮杂环配体经历了N-和C-烷基化反应。     

一类六核三价铁簇化合物的合成及结构表征

选择3种不同尺寸含氮配体（哌嗪、咪唑和三氮唑）与三羟甲基丙烷（H₃tmp）和FeCl₃采用溶剂热反应合成3例六核Fe（Ⅲ）合物：（C₅H₁₄N₂）[Fe₆（μ₆-O） Cl₆（tmp）₄]·2H₂O·CH₃OH（1）、（C₃H₅N₂）₂[Fe₆（μ₆-O） Cl₆（tmp）₄]（2）和（C₄H₈N₃）₃（C₂H₄N₃）[Fe₁₂（μ₆-O）₂Cl₁₂（tmp）₈]·3CH₃OH（3）,并对它们的结构进行表征。发现三元醇配体有利于合成高核金属簇。3个化合物具有相同的阴离子簇[Fe₆（μ₆-O） Cl₆（tmp）₄]^2-。通过晶体学参数,元素分析,红外等手段证实,在化合物1和3的体系中,氮杂环配体经历了N-和C-烷基化反应。     

由联苯四羧酸配体构筑的一维锰(Ⅱ)和二维铜(Ⅱ)配位聚合物的合成、晶体结构及磁性质

采用水热方法,用2种联苯四羧酸配体（2,4-H₄bpta和3,5-H₄bpta）和4,4''-联吡啶（4,4''-bipy）或2,2''-联吡啶（2,2''-bipy）分别与MnCl₂·4H₂O和CuCl₂·H₂O反应,合成了一个具有一维双螺旋链结构的配位聚合物[Mn（μ₃-2,4-H₂bpta）（4,4''-bipy）₂]_n（1）和一个二维层状配位聚合物{[Cu（μ4-3,5-bpta）_0.5（2,2''-bipy）（H₂O）]·H₂O}_n（2）,并对其结构和磁性质进行了研究。结构分析结果表明2个配合物分别属于单斜晶系,P2₁/c和C2/c空间群。配合物1具有一维双螺旋链结构,而且这些一维链通过O-H…N氢键作用进一步形成了二维超分子网络。而配合物2具有二维层状结构。研究表明,配合物1中相邻锰离子间存在铁磁相互作用。     

由联苯四羧酸配体构筑的一维锰(Ⅱ)和二维铜(Ⅱ)配位聚合物的合成、晶体结构及磁性质

采用水热方法,用2种联苯四羧酸配体（2,4-H₄ bpta和3,5-H₄ bpta）和4,4''-联吡啶（4,4''-bipy）或2,2''-联吡啶（2,2''-bipy）分别与MnCl₂·4H₂O和CuCl₂·H₂O反应,合成了一个具有一维双螺旋链结构的配位聚合物[Mn（μ₃-2,4-H₂bpta）（4,4''-bipy）₂]_n（1）和一个二维层状配位聚合物{[Cu（μ₄-3,5-bpta）_0.5（2,2''-bipy）（H₂O）]·H₂O}_n（2）,并对其结构和磁性质进行了研究。结构分析结果表明2个配合物分别属于单斜晶系,P2₁/c和C2/c空间群。配合物1具有一维双螺旋链结构,而且这些一维链通过O-H…N氢键作用进一步形成了二维超分子网络。而配合物2具有二维层状结构。研究表明,配合物1中相邻锰离子间存在铁磁相互作用。     

基于醚氧桥联四羧酸配体构筑的铜(Ⅱ)/钴(Ⅱ)/镍(Ⅱ)配位聚合物的合成、结构和在Knoevenagel缩合反应中的催化性质

采用水热方法,选用醚氧桥联羧酸配体2,3'',4,4''-二苯醚四羧酸（H₄deta）与2,2''-联吡啶（2,2''-bipy）、4,4''-联吡啶（4,4''-bipy）分别与CuCl₂·2H₂O、CoCl₂·6H₂O和NiCl₂·6H₂O在160℃下反应,得到了3个配位聚合物：二维层结构的{[Cu₂（μ₅-deta）（2,2''-bipy）₂]·2H₂O}_n （1）、一维链结构的[Co₂（μ₄-deta）（2,2''-bipy）₂（H₂O）₃]_n （2）和三维网络结构的{[Ni₂（μ₃-deta）（μ-4,4''-bipy）_2.5（H₂O）₅]·3H₂O}_n （3）,并对其结构和催化性质进行了研究。研究表明,在室温下化合物1在Knoevenagel缩合反应中显示出很好的催化活性。     

由联苯三羧酸和含氮配体构筑的钴(Ⅱ)、铅(Ⅱ)和锌(Ⅱ)配合物的合成、晶体结构及荧光性质

采用水热方法，用联苯三羧酸配体（H₃btc）和菲咯啉（phen）或2，2''-联吡啶（2，2''-bipy）分别与CoCl₂·6H₂O、PbCl₂和ZnCl₂反应，合成了一个单核配合物[Co（Hbtc）（phen）₂（H₂O）]·3H₂O（1）以及2个一维链状配位聚合物[Pb（μ₃-Hbtc）（2，2''-bipy）]_n（2）和{[Zn₃（μ₂-btc）₂（μ₂-H₂O）（2，2''-bipy）₃（H₂O）₅]·8H₂O}_n（3），并对其结构和荧光性质进行了研究。结构分析结果表明3个配合物分别属于正交和三斜晶系，Pna2₁和P1空间群。配合物1具有零维单核结构，而且这些单核钴单元通过O-H…O氢键作用进一步形成了三维超分子框架。而配合物2和3具有基于双核单元的一维链结构。研究表明，配合物2和3在室温下能发出蓝色荧光。     

由4,4'-二甲基-2,2'-联苯二甲酸配体构筑的锌(Ⅱ)和镉(Ⅱ)双核配合物的合成、晶体结构、荧光及光催化性质

采用水热方法，用4，4''-二甲基-2，2''-联苯二甲酸配体（H₂dbda）和菲咯啉（phen）、2，2''-联吡啶（2，2''-bipy）分别与ZnCl₂或Cd-Cl₂·H₂O反应，合成了3个零维双核配合物[Zn₂（μ-dbda）₂（phen）₂（H₂O）₂]（1）、[Zn₂（μ-dbda）₂（2，2''-bipy）₂]（2）和[Cd₂（μ-dbda）₂（2，2''-bipy）₂（H₂O）₂]·2H₂O（3），并对其结构、荧光和光催化性质进行了研究。结构分析结果表明3个配合物分别属于三斜和单斜晶系的P1和P2₁/n空间群。配合物1~3都具有零维双核结构，而且这些双核单元通过O-H…O氢键作用进一步形成了三维超分子框架。研究表明，配合物1~3在室温下能发出蓝色荧光。另外，研究了3个配合物对有机染料亚甲基蓝的光催化降解性能，结果表明配合物3可以高效地降解亚甲基蓝。     

3,3''-(吡啶-3,5)二苯甲酸构筑的Co(Ⅱ)/Ni(Ⅱ)配合物的合成、晶体结构及性质

设计、合成了2个配合物：{[Co₂（pddb）₂（μ₂-H₂O）（H₂O）₂]·2DMA·5H₂O}_n（1）和{[Ni₂（pddb）₂（μ₂-H₂O）（H₂O）₂]·2DMA·5H₂O}_n（2）（H₂pddb=3，3''-（吡啶-3，5）二苯甲酸，DMA=N，N-二甲基乙酰胺），并通过红外光谱（IR），元素分析，热重分析（TG）和单晶X射线衍射确定它们的结构。结构分析表明1和2是异质同构的，其空间构型可简化成（3，6）连接的拓扑结构，其符号为（4²·6）·（4⁴·6²·8⁸·10）。进一步研究了配合物1和2的固体紫外、磁性及其催化性能。研究表明1和2中的中心金属离子之间存在反铁磁耦合作用，并且1可以作为C-H活化的高效非均相催化剂。     

由醚氧桥联羧酸配体构筑的铜(Ⅱ)、锌(Ⅱ)和锰(Ⅱ)配位聚合物的合成、晶体结构、荧光及光催化性质

采用水热方法,用醚氧桥联的三羧酸配体（H₃dpna）和四羧酸配体（H₄deta）为主配体,2,2''-联吡啶（2,2''-bipy）和菲咯啉（phen）为辅助配体,分别与CuCl₂·H₂O、ZnCl₂和MnCl₂·4H₂O反应,合成了2个二维配位聚合物{[Cu₃（μ₄-dpna）₂（2,2''-bipy）₂]·4H₂O}_n（1）和{[Zn₃（μ₄-dpna）₂（2,2''-bipy）₂（H₂O）₂]·6H₂O}_n（2）以及2个一维配位聚合物{[M₂（μ₄-deta）（phen）₂（H₂O）]·3H₂O}_n（M=Mn（3）,Zn（4））,并对其结构、荧光和光催化性质进行了研究。结构分析结果表明配合物1和2属于单斜晶系,P2₁/c和C2/c空间群。由于采用了不同的金属离子,配合物1和2呈现不同的二维层结构。配合物3和4为异质同心结构,均属于单斜晶系,P2₁/n空间群。配合物3和4都具有一维链结构。另外,研究了这些配合物的荧光和对有机染料亚甲基蓝的光催化降解性能,结果表明配合物2和4可以高效地降解亚甲基蓝。     

以5-(3-吡啶基)-1H-吡唑-3-羧酸为配体的钴共晶配合物的合成、晶体结构及电化学性质

采用溶剂热法合成了一种新型的钴（Ⅱ）基配合物,即{[Co（Hppc）₂][Co₂（4,4''-bipy）（H₂O）₄]（SO₄）₂·2H₂O}_n （1）,其中H₂ppc=5-（3-吡啶基）-1H-吡唑-3-羧酸,4,4''-bipy=4, 4''-联吡啶。配体H₂ppc是由吡啶环、吡唑环和羧基共同组成,同时兼具了刚性和柔性。通过单晶X射线衍射对配合物1进行了结构测定。结果显示所合成的配合物1结晶在单斜晶系C2/c空间群,包括2个晶体学独立部分：二维层状[Co（Hppc）₂]和一维链状[Co₂（4,4''-bipy）（H₂O）₄]^2-,并形成具有{4⁴·6²}{4}₂拓扑网络结构的共晶化合物。此外,配合物1呈现出良好的电化学发光（ECL）性能以及良好的超级电容器性能。     

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%.     

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.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

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.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.