Two-photon absorption in V-type chromophores with electron-rich heterocyclevinylene bridges

A series of V-type chromophores with electron-rich heterocyclevinylene bridges have been synthesized via Wittig-Horner-Emmons and Vilsmeier reactions.All the target chromophores showed strong one-photon and two-photon excited emission,and their electron properties could be tuned by using different heterocycles such as furan,thiophene and pyrrole moieties in I-III.The maximum two-photon absorption (TPA) cross sections occurred at 760 nm and were measured to be in the range of 400-800 GM.     

含芳香稠环或杂环的光致变色螺吡喃化合物的光谱性能及与DNA作用研究

研究9种带有芳香稠环或杂环基团的光致变色螺吡喃化合物的光致变色性能和荧光性质.通过紫外-可见吸收光谱和荧光光谱对该类化合物与DNA相互作用性能进行了初步探讨.     

Reaction of carbon disulfide with 2-bromoimidazolium salts. Novel bicyclic mesoionic thiazolo[3,2-a]imidazoles

A new class of thiazolo[3,2-a]imidazole derivatives is obtained in good yields, by reacting 1-methyl-2-bromoimidazolium salts bearing N⁺-CH₂COAr, N⁺-CH₂COMe, N⁺-CH₂COOMe, or N⁺-CH₂CN fragments, with carbon disulfide in the presence of Et₃N at room temperature. The mesoionic structures of these compounds are established by NMR spectroscopy and by single-crystal X-ray analysis.     

New Core-Expanded Naphthalene Diimides for n-Channel Organic Thin Film Transistors

Four classes of core-expanded naphthalene diimides （la, lb, 2a, 2b, 3 and 4） that bear different elec- tron-deficient sulfur heterocycles were designed and synthesized. The solution-processed thin films of la, 2a, 3 and 4 operated well in air as n-channel organic transistors with electron mobility ranging from MO 6 to 0.14 cm2/Vs, depending on the different conjugated backbones. The thin film microstructure studies were also carried out to un- derstand the variations of the electron mobility for thin films of la, 2a, 3 and 4.     

Recent advancement in the synthesis of 1,2- and 2,1-benzothiazines

1,2- and 2,1-benzothiazines, for example, 1,2-benzothiazine-1,1-dioxides. 2,benzothiazine-2,2-dioxides, 1-alkyl/aryl-1,2-/2,1-benzothiazine-S-oxides, dibenzothiazine and polyheterocycle containing benzothiazine moiety are considered to be one of the privileged heterocyclic scaffolds with huge importances both in synthetic organic chemistry and medicinal chemistry especially in the drug industry. Numerous pioneering methodologies for asymmetric and non-asymmetric scaffold constructions have been developed. Comprehensive visions of different powerful methodologies for the synthesis of these scaffolds have been presented in this review.     

Synthesis,Characterization, and Antimicrobial Evaluation of Quinoline-Oxadiazole–Based Azetidinone Derivatives

A series of 3-chloro-1-(aryl)-4-(2-(2-chloroquinolin-3-yl)-5-(pyridin-4-yl)-1,3,4-oxadiazol-3(2H)-yl)-4-ethyl-azetidin-2-ones (5a–l) have been synthesized and characterized by IR, ¹H NMR, and¹³C NMR. Synthesized compounds were screened for their antimicrobial activity against different strains of bacteria (E. coli, P. aeruginosa, S. aureus, S. pyogenes, C. albicans, A. niger, and A. clavatus). On the basis of statistical analysis, it has been observed that compounds had significant correlations.     

X射线单晶衍射研究系列功能七元杂环桥联联苯构象

含有七元杂环桥联联苯的π-共轭聚合物是重要的宽禁带光电材料, 其发光性质决定于两苯环间扭曲角. 利用X射线单晶衍射仪确定了系列功能的七元杂环桥联联苯化合物的晶体结构, 比较了桥联原子, 6,6位取代基及分子间弱氢键对这类桥联联苯扭曲构象的影响. 桥联键是—CH2—O—CH2—和—CH2—S—CH2—的七元杂环桥联联苯两苯环间的扭曲角分别为39°和51°, 在6,6位上含有不同取代基的双氧桥联七元杂环桥联联苯的扭曲角存在5°的差异. 在双氧桥联的七元杂环桥联联苯的二聚物中, 桥联的氧原子与非桥联的苯亚基-苯亚基2,2’位置上的两个氢原子之间形成的氢键网络结构导致中心联苯呈现平面构象, 但氢键并没有改变桥联联苯的构象. 七元杂环桥联联苯的构象主要由桥联原子决定, 同时分子间相互作用亦能轻微调控这类桥联联苯的扭曲角.     

单质碘促进的有机反应研究进展

单质碘作为有机化学中结构最为简单的反应试剂之一,其促进的有机转化在最近几年越来越受到人们的关注.总结了单质碘的氧化性,酸性和亲电性3类基本化学性质,并针对3类性质所涉及的相关反应性报道进行了介绍.除此之外,还总结了近5年来单质碘作为催化剂在杂环合成,偶联反应,及C—H官能团转化等方面的应用.