一种大斯托克斯位移的红光发射荧光探针选择性检测次氯酸

设计、合成了一种基于巴比妥酸衍生物的具有D-π-A结构的光学探针3。该探针能够作为一种高度灵敏和选择性的次氯酸指示剂,快速实现对次氯酸的比色和荧光信号(开-关)的双响应(约15 s)。推测的响应机制是ClO^-与C=C之间发生了亲电加成和氧化裂解反应,导致探针的D-π-A结构遭到破坏,从而阻断了其分子内电荷转移(intramolecular charge transfer,ICT)进程。探针只需一步即可合成,同时具有红光发射(628 nm)和较大的斯托克斯位移(158 nm),检测限(limit of detection,LOD)低至14 nmol·L^-1。此外,探针还表现出低细胞毒性,并成功应用于活细胞成像。     

非对称双极性(D-π-A)吡啶Salophen席夫碱锌/镍配合物的合成、表征、线性及非线性光学性质研究

通过Still偶联反应合成了吡啶取代的香草醛(1a和1b)。以过渡金属离子(Zn²⁺和Ni²⁺)作为模板,以单亚胺席夫碱2和吡啶基香草醛为原料合成和表征了新的非对称双极性(D-π-A)Salophen金属配合物(3a、3b和3c)。测定了这些金属配合物的线性和三阶非线性光学(双光子吸收,TPA)性质。双极性的Salophen金属配合物的发射光谱在可见光范围内(486~516nm),荧光寿命4.51ns~5.18ns,荧光量子产率在4.3%~5.3%之间。衰减时间测试表明,荧光寿命是在纳秒级范围,这表明该发射来自单线态。对这些化合物进行了热重分析,结果表明3a、3b和3c都是热稳定的,起始分解温度(T_d)为333~374℃。使用开孔Z-扫描方法在800nm处用100fs脉冲的激光对这些双极性的Salophen金属配合物的TPA截面σ⁽²⁾进行了测试,最高可达1403GM,其值为目前已知席夫碱金属配合物较高值之一。测试表明,锌的Salophen金属配合物具有良好的荧光量子产率、巨大的TPA截面σ⁽²⁾、很高的热稳定性以及锌配合物公认的低毒性。因这些配合物可以被近红外或红外波长的光激发,这种光可以有效地穿透生物组织同时减轻细胞损伤,所以Salophen锌配合物作为双光子荧光发色团在生物体成像中有潜在的应用。     

基于烟酰腙Schiff碱的Cu(Ⅱ)和Ni(Ⅱ)配合物的合成、晶体结构和性质

采用缓慢挥发法合成了2个烟酰腙类Schiff碱配合物[Cu(Py)(HL¹)]₂ (1)和[Ni(L²)₂] (2), 其中, H₃L¹=2, 4-二羟基苯甲醛缩烟酰腙, HL₂=2-乙酰基吡啶缩烟酰腙。采用元素分析、红外光谱、紫外光谱、荧光光谱和热重分析以及X-射线单晶衍射分析进行了表征。结果表明, 1和2的晶体均属单斜晶系, P2₁/c空间群;1的晶胞参数a=0.739 86(12) nm, b=1.903 7(3) nm, c=1.154 86(19) nm, β=105.090(3)°, V=1.570 5(4) nm³;该化合物是中心对称的双核配合物, 每个Cu(Ⅱ)离子都处于畸变四方锥配位环境;结构基 元通过π-π相互作用和O-H…N氢键形成三维超分子。2的晶胞参数a=2.034 0(5) nm, b=1.183 2(3) nm, c=1.020 7(3) nm, V=2.456 1(11) nm³;中心离子Ni(Ⅱ)的配位数为6, 它处于畸变八面体配位环境。配合物有很高的热稳定性, 分解温度分别为315 ℃ (1)和358 ℃ (2)。     

氰基羧酸二茂铁配体及其有机锡配合物的合成与光电性质

设计合成了一种D-π-A型(Donor-π-Accept)氰基羧酸二茂铁配体,它与有机锡化合物二丁基氧化锡(n-Bu₂SnO)反应,得到了一种新型二茂铁有机锡羧酸酯配合物。通过¹H NMR、¹¹⁹SnNMR、IR、FT-IR、UV-Vis和元素分析等对配体及其配合物进行了全面的表征,利用X-射线单晶衍射测定了配合物的晶体结构,运用CV和Z-scan测试方法系统地研究了它们的电化学和双光子吸收性质。结果表明：与配体相比较,配合物更难被氧化,且具有更大的双光子吸收截面。     

基于环己二酸和双苯并咪唑配体的一维钴(Ⅱ)配位聚合物的合成、结构和催化性能研究

水热条件下,合成了钴(Ⅱ)配位聚合物{[Co(L)(chdc)]·2H₂O}_n (1) (L=1,3-二(苯并咪唑-1-甲基)苯,H₂chdc=1,4-环己烷二酸)。结构分析表明,配合物1的晶体属于单斜晶系,C2/c空间群,晶胞参数为a=1.4504(1) nm,b=1.834 9(2) nm,c=2.128 7(2) nm,β=94.325(1)°,V=5.649 2(9) nm³,Z=4。该配合物为一维环状链结构,并进一步通过链间的π-π作用自组装成二维超分子结构。配合物1作为类芬顿反应的催化剂降解刚果红显示较高的活性。     

2-[(2-溴苯胺基)甲基]-4-氯苯酚Schiff碱及其铜配合物的合成及晶体结构

以5-氯水杨醛和邻溴苯胺为原料合成了一种新的Schiff碱配体2-[(2-溴苯胺基)甲基]-4-氯苯酚(1)(C₁₃H₉BrClNO,H₂L),继而与过渡金属铜离子配合,得到其配合物2 ([Cu(C₁₃H₈BrClNO)₂],CuL₂)。通过X-射线衍射法对配体及其配合物进行了结构表征。化合物1属正交晶系,Pbca空间群,晶胞参数a=0.710 19(12) nm,b=1.308 2(2) nm,c=2.533 3(5) nm,M_r=310.57,V=2.353 6(7) nm³,D_c=1.753 g·cm^-3,Z=8,μ=3.700 mm^-1,Z=8,F(000)=1 232,R=0.025 0,wR=0.055 5;化合物1依靠分子间的C-H…N,C-H…O,C-H…Cl 氢键及π-π堆积作用进一步联结成二维网状结构。化合物2属单斜晶系,P2₁/c空间群,晶胞参数a=0.956 8(2) nm,b= 1.085 3(3) nm,c=1.204 7(3) nm,β=105.965(7)°,M_r=682.67,V=1.202 8(6) nm³,D_c=1.885 g·cm^-3,Z=2,μ=4.481 mm^-1,F(000)=670,R=0.045 0,wR=0.122 5。2依靠分子间C-H…π作用及卤素…卤素作用进一步联结成三维网状结构。     

CH/π, CH/O弱氢键在2,6-二(α-苯基苄基)-1,5-萘二酚主体分子包结物构筑中的作用

设计、合成了一种新的主体分子2,6-二(α-苯基苄基)-1,5-萘二酚 (1). 它可与许多有机小分子形成配位包合物. 用IR和¹H NMR表征了配位包结物, 并测定了主客体分子的摩尔比: 1•DMF (1∶1), 1•DMSO (1∶2), 1•吡啶 (1∶1), 1•喹啉(1∶2), 1•N-甲基吡咯烷酮(1∶1). 用单晶X衍射分析了包结物 (1)•DMF的晶体结构, 属三斜晶系, 晶胞参数为P-1, a＝0.9085(9) nm, b＝0.9501(6) nm, c＝2.0995(6) nm, α＝99.59(3)°, β＝90.13(4)°, γ＝96.20(7)°, V＝1.776(2) nm³, D_c＝1.898 g•cm^－3. 结果表明, 主体分子间的CH/π弱氢键在决定主体分子的层状框架结构和客体分子在层间的填充方式中发挥了重要作用; 两种不等效的客体分子与主体分子的作用方式是不同的, 一种客体分子是通过CH/π, CH/O弱氢键与同层的不同主体分子相互作用, 另一种是通过CH/π, CH/O弱氢键与相邻层的不同主体分子相互作用.     

DDQ/PPh3催化的N-苯甲酰苯胺衍生物中间体的有效合成及晶体结构

在DDQ/PPh₃作用下,以2-异丙基苯甲酸或水杨酸为原料,在温和条件下以较高的收率合成、分离得到两个化合物(2)和(3)。化合物(2)和(3)与苯胺在氯仿中加热回流可分别转化为酰胺类化合物(4)和(5)。所有化合物通过元素分析、质谱、核磁共振进行了表征,并解析了化合物(2)和(3)的X-衍射单晶结构。化合物1,2-二(2-异丙基苯甲酸)-2,3-二氰-5,6-二氯苯(2)晶体属单斜晶系,空间群P2₁/c,其晶胞参数为：a=1.2875(3)nm,b=1.5186(2)nm,c=1.5726(3)nm,β=122.23(3)°,V=2.6010(1)nm³,D_c=1.331g·cm^-3,Z=4,F(000)=1080,R₁=0.0572,wR₂=0.1260;化合物1,2-二(2-羟基苯甲酸)-2,3-二氰-5,6-二氯苯(3)晶体属三斜晶系,空间群P1,其晶胞参数为：a=0.87776(16)nm,b=1.13111(15)nm,c=1.18639(17)nm,α=69.290(2)°,β=89.409(3)°,γ=67.878(2)°,V=1.0104(3)nm³,D_c=1.542g·cm^-3,Z=2,F(000)=476,R₁=0.0383,wR₂=0.0931。强π-π堆积作用和分子间氢键将化合物(2)和(3)组装成稳定的三维结构。     

二维网状Pb(Ⅱ)配合物的合成、晶体结构及荧光性质

利用4-吡啶-3-苯甲酸(4,3-pybz)和醋酸铅在水热条件下合成了一种新型金属配合物[Pb(4,3-pybz)2]_n(1),并对其进行了元素分析、红外光谱、热重表征、X 射线单晶衍射测定。该配合物为正交晶系,Pccn空间群,a=1.070 74(7) nm,b=2.138 03(13) nm, c=0.865 65(5) nm,V=1.981 7(2) nm³,Z=4,D_c=2.023 Mg·m^-3,F(000)=1 152,GOF=1.050,μ=8.549 mm^-1,残差因子R₁=0.013 9,wR₂=0.032 4。该配合物展现了一个具有(4,4)拓扑二维波浪状网络结构,进而通过弱的π-π相互作用拓展为三维超分子体系。此外,室温下配合物1展现了弱的荧光性质。     

两个Schiff碱铜配合物的合成、晶体结构、光谱性质及取代基效应

合成了2个含肟基Schiff碱Cu(Ⅱ)配合物[Cu(L¹)₂](1)和[Cu(L²)₂](2)(HL¹=1-(3-((2-hydroxybenzylidene)amino) phenyl) ethanone O-benzyl oxime; HL²=1-(3-((2-Hydroxy-naphthalen-1-ylmethylene)-amino)-phenyl)-ethanone oxime),并通过元素分析、红外光谱、紫外光谱,荧光光谱及X射线单晶衍射分析进行了表征和分析。结果表明,配合物1和2具有相似的结构,均由1个中心Cu(Ⅱ)离子和2个双齿配体单元组成,且Cu(Ⅱ)离子的配位数为4,具有平面四边形结构。配合物1和2均形成了二维层状超分子结构,不同的是配合物1通过分子间π…π堆积作用相连接,而配合物2通过分子间O-H…N和C-H…π氢键作用而形成了超分子结构。进一步讨论了配合物1的荧光性质及两个配合物间配体的取代基效应。     

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.     

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.     

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.     

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.     

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.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

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.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

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.