基于N-乙酸基-5-氧烟酸的两个Pb（Ⅱ）配位聚合物的合成、晶体结构与荧光性质

采用水热法合成了2个以N-乙酸基-5-氧烟酸（H₂L）为配体的铅金属-有机配位聚合物：[Pb₄（μ₃-O）₂L₂]_n（1）和[Pb₃（μ₄-O）₂L]_n（2）。通过元素分析、红外光谱和X射线单晶衍射进行了结构表征。结构分析表明,聚合物1属单斜晶系,C2/c空间群,其由[Pb₄（μ₃-O）₂]_n构成的刚性无机链通过配体L^2-连接成三维网络结构。聚合物2属正交晶系,P2₁2₁2₁空间群,其三维结构由[Pb₃（μ₄-O）₂]_n构成的无机金属链与配体L^2-相互连接形成。研究了2的热稳定性及其在室温下的固体荧光性质。     

以3,5-二（吡啶-4-甲氧基）苯甲酸为配体构筑的两个钡（Ⅱ）、铅（Ⅱ）配位聚合物

以3,5-二（吡啶-4-甲氧基）苯甲酸（HL）为配体合成了2个配合物：[BaL₂]_n（1）和[PbL（Ox）_0.5]_n（2）（H₂（Ox）为草酸）,并通过元素分析,红外光谱,热重和X-射线单晶衍射实验对其结构进行了表征。分析表明,1由L^-连接形成二维结构,通过苯环之间的π…π作用连接成三维网络结构;2由于主配的连接形成二维层状结构,再通过辅配连接形成拓扑符号为（4³）（4⁴.5.6¹⁷.7².8²）（4.5²）的三维网络结构。     

联苯-2,4,4',6-四甲酸银、咪唑-菲啰啉-苯氧乙酸镉配位聚合物的合成、结构及与DNA的相互作用

由联苯-2,4,4'',6-四甲酸（H₄BPTC,C₁₆H₁₀O₈）和2-4-（1H-咪唑-2-[4,5-f] [1,10]菲啰啉基）苯氧乙酸（HPIMPHC,C₂₁H₁₄N₄O₃）,水热合成了2种新型配位聚合物[Ag₄（BPTC）]_n（1）,[Cd（PIMPHC）₂]_n（2）。用元素分析、红外光谱、热重分析和X射线单晶衍射对配合物进行了表征和结构分析。配合物 1 属三斜晶系,空间群为P1;Ag（Ⅰ）的配位数分别为4、3、2,配位构型为变形四面体、平面三角形和V型。配合物2属正交晶系,空间群为Pbcn;Cd（Ⅱ）的配位数为6,配位构型为变形的八面体,Cd（Ⅱ）离子间通过三齿配体 PIMPHC^-桥连,形成2D网状结构。用EtBr荧光探针法研究了配体及配合物与ct-DNA的相互作用。     

咪唑-菲咯啉-苯氧乙酸锌、铅配合物的合成,结构及与DNA的相互作用

以2-4-(1H-咪唑-2-[4,5-f] [1,10]菲咯啉基)苯氧乙酸(HPIMPHC)和2-2-(1H-咪唑-2-[4,5-f] [1,10]菲咯啉基)苯氧乙酸(HOIMPHC)为配体,水热合成了2种新型配合物[Zn(PIMPHC)₂]_n (1)和{[Pb(OIMPHC)₂]·4H₂O}_n (2)。配合物1属正交晶系,空间群为Pbcn;Zn(Ⅱ)的配位数为6,配位构型为变形的八面体,形成2D网状结构。配合物2属单斜晶系,空间群为P2₁/n;Pb(Ⅱ)的配位数为7,配位构型为变形的五角双锥,形成2D网状结构。荧光光谱的结果表明,配合物与DNA的相互作用强于配体。     

基于反-双(β-二酮)-1,4-环己二胺的席夫碱Hg(Ⅱ)配位聚合物的合成与晶体结构

合成了反1,4-环己二胺桥联β-二酮的席夫碱配体L1（反-双（乙酰丙酮）-1,4-环己二胺）和L2（反-双（苯甲酰丙酮）-1,4-环己二胺）,然后将配体L1和L2分别与HgCl₂、HgI₂进行配位反应,得到4个Hg（Ⅱ）配合物：[Hg₂（L1）Cl₄]_n（1）,{[Hg₂（L2）Cl₄]·L2}_n（2）,[Hg₂（L1）I₄]_n（3）,[Hg₂（L2）I₄]_n（4）。并通过元素分析、红外光谱、粉末衍射、单晶X射线衍射等对配合物的结构进行了表征。在固体状态下,配合物1和2的Hg（Ⅱ）离子与配体中的γ-C原子及3个氯离子配位形成1D链结构,配合物3的Hg（Ⅱ）离子与L1配体中的烯醇式氧原子,以及3个碘离子配位形成2D网状结构,配合物4的Hg（Ⅱ）离子与配体L2中的烯醇式氧原子及3个碘离子配位形成1D链结构。     

两个基于β-二酮配体构筑的银配位聚合物的合成和晶体结构

以配体3-（（5-（3-吡啶基）-2-（1,3,4-噁二唑基））硫代）-2,4-戊二酮（L₁）与AgSbF₆进行配位反应,得到配位聚合物{[Ag（L₁）₂]SbF₆}_n （1）;以配体3-（（5-（4-吡啶基）-2-（1,3,4-噁二唑基））硫代）-2,4-戊二酮（L₂）与AgCF₃SO₃进行配位反应,得到配位聚合物[Ag（L₂）（CF₃SO₃）]_n （2）。并通过粉末X射线衍射、红外光谱、元素分析和单晶X射线衍射对配合物的结构进行了表征。在固体状态下,配位聚合物1和2都形成1D链状结构。     

基于反-双(β-二酮)-1,4-环己二胺的席夫碱Hg(II)配位聚合物的合成与晶体结构

合成了反1,4-环己二胺桥联β-二酮的席夫碱配体L1（反-双（乙酰丙酮）-1,4-环己二胺）和L2（反-双（苯甲酰丙酮）-1,4-环己二胺）,然后将配体L1和L2分别与HgCl₂、HgI₂进行配位反应,得到4个Hg（Ⅱ）配合物：[Hg₂（L1）Cl₄]_n（1）,{[Hg₂（L2）Cl₄]·L2}_n（2）,[Hg₂（L1）I₄]_n（3）,[Hg₂（L2）I₄]_n（4）。并通过元素分析、红外光谱、粉末衍射、单晶X射线衍射等对配合物的结构进行了表征。在固体状态下,配合物1和2的Hg（Ⅱ）离子与配体中的γ-C原子及3个氯离子配位形成1D链结构,配合物3的Hg（Ⅱ）离子与L1配体中的烯醇式氧原子,以及3个碘离子配位形成2D网状结构,配合物4的Hg（Ⅱ）离子与配体L2中的烯醇式氧原子及3个碘离子配位形成1D链结构。     

基于吡啶二羧酸配体的稀土配合物的合成、结构及性质

以2,6-二甲基吡啶-3,5-二羧酸（H₂L₁）为主配体,1,10-菲咯啉（L₂）为辅配体,分别与五水合硝酸镝、六水合硝酸铽及六水合硝酸铕通过水热法合成[Dy₂（L₁）₃（L₂）₂]_n（1）、{[Tb₂（L₁）₃（L₂）₂]·5H₂O}_n（2）和{[Eu₂（L₁）₃（L₂）₂]·5H₂O}_n（3）三种配合物。通过单晶X射线衍射、红外光谱、荧光光谱和热重分析对其结构进行了表征与性质研究。结果表明,配合物1~3均以稀土离子为金属节点连接配体L₁^2-和L₂,形成无限延伸的一维链状结构。     

三个基于柔性4-取代双三唑配体锌配位聚合物的合成、晶体结构

以1,2-二（4H-1,2,4-三唑）乙烷（btre）和3个二元羧酸1,3-金刚烷二酸（H₂adc）、对苯二甲酸（1,4-H₂bdc）和邻苯二甲酸（1,2-H₂bdc）为配体,在室温下合成了3个锌配位聚合物{[Zn（μ₂-btre）（μ₂-adc）]H₂O}_n（1·H₂O）、[Zn₂（μ₂-btre）（μ₂-1,4-bdc）₂（H₂O）₂]_n（2）和[Zn（μ₂-btre）（μ₂-1,2-bdc）]_n（3）。测试了3个配合物的晶体结构,并用红外光谱、元素分析和粉末衍射对其进行表征。晶体结构测试表明,1为2D（4,4）网格结构,π-π作用将相邻的2D网格连接成3D结构。配合物2和3分别是3D和2D（4,4）网格结构。另外,研究了3个配合物的热稳定性和室温下的固体荧光。     

基于N-((3-吡啶基)磺酰基)天冬氨酸的Co(Ⅱ)、Zn(Ⅱ)、Cd(Ⅱ)配位聚合物的合成、磁性和荧光性质

以N-（（3-吡啶基）磺酰基）天冬氨酸（H₂L）为配体,采取水热合成的方法,合成了配位聚合物[M（HL）₂]_n （M=Co,1;Zn,2;Cd,3）。X射线单晶衍射分析表明,它们的晶体同构。1的磁性分析表明,1的Curie常数为4.66 cm³·mol^-1·K,Curie-Weiss常数为 -21.23 K;与配体H₂L相比,2和3的发射光谱发生了明显的蓝移,可能归因于配体到金属的电荷转移。     

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.     

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.     

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.     

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.     

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.     

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.     

Microwave-assisted copper-catalyzed stereoselective ring expansion of three-membered heterocycles with α-diazo-β-dicarbonyl compounds

Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular S_N2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.     

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.