Ratiometric Fluorescent Chemosensor for Selective Detection Cr3+ based on Carbazole and Benzimidazole

A novel Cr³⁺‐selective ratiometric fluorescent chemosensor 1‐substitued‐2‐carbazoleylbenzoimidazole ( L ) based on benzimidazole and carbazole was synthesized and characterized by nuclear magnetic resonance (¹H/¹³C NMR), Fourier transform infrared spectrometry (FTIR), and mass spectroscopy. L could selectively detect Cr³⁺ over other metal ions by UV–vis absorption and fluorescence emission spectroscopic methods in CH₃CN. L showed ratiometric fluorescent recognition of Cr³⁺; the fluorescent responses could be observed by naked eye under a UV lamp. The binding stoichiometry ratio of the L –Cr³⁺ complex was found to be 1:1 according to Job’s plot and MALDI‐TOF MS analysis. The results of DFT calculation supported this conclusion.     

咔唑-9-乙氧基碳酰肼柱前衍生中性糖的高效液相色谱分析

采用一种新型紫外、荧光衍生试剂咔唑-9-乙氧基碳酰肼(EEOC-Hydrazlde)对5种中性糖(乳糖,甘露糖,葡萄糖,鼠李糖和山梨糖)进行柱前衍生,并通过紫外、荧光检测的方法进行高效液相色谱(HPLC)分析。结果表明：反应温度65℃,时间6．5h,醋酸含量为3．5％(V／V)的条件下,衍生产率可达最大。衍生物的激发和发射波长为λex／λem=293／360nm,紫外检测波长254nm。检出限范围15-60fmol。该方法具有检测灵敏度高,衍生化反应简单,适合糖类化合物的分析。     

Synthesis of substituted carbazoles and β-carbolines by cyclization of diketoindole derivatives

A new route to substituted β-carbolines and carbazoles is described. Diketoindole intermediates, prepared by Friedel-Crafts acylations of 3-substituted indoles, have been converted to 3-hydroxycarbazoles and β-carbolines in good yields, 51-96% and 82-97%, respectively. This method also allows for the formation of 4-substituted β-carbolines. The application of this methodology to the synthesis of the natural products hyellazole and 6-chlorohyellazole is also described.     

Multifunctional red phosphorescent bis-cyclometallated iridium complexes based on 2-phenyl-1,2,3-benzotriazole ligand and carbazolyl moieties

Multifunctional phosphorescent bis-cyclometallated iridium(III) complexes based on the 2-phenyl-1,2,3-benzotriazole moiety and bearing branched hole-transporting carbazole fragments were synthesized. The isolated compounds were found to be amorphous and expressed very good solubility. Introduction of flexible aliphatic chains of various lengths into the iridium complexes enabled manipulation of their glass transition temperature. The iridium complexes exhibited red phosphorescence emission at 650 nm with the lifetime of 5.7 μs and phosphorescence quantum yields of 0.22 and 0.17 in solution and solid state, respectively, at room temperature. The shielding effect of the carbazolyl moieties on the concentration quenching of phosphorescence of the iridium centers was found to result in the increased excited state lifetime and quantum yield due to the suppressed exciton migration. Non-optimized OLED devices, based on the phosphorescent bis-cyclometallated iridium(III) complex without host material were fabricated and their electroluminescence properties were evaluated.     

Stable deep blue organic light emitting diodes with CIE of y < 0.10 based on quinazoline and carbazole units

Achieving stable deep blue organic light emitting diodes (OLEDs) with narrow full width at half maximum (FWHM) and color gamut in the range of the commission International de L’Eclairage (CIE) of y ≤ 0.10 is still challenging in display and lighting applications. In this investigation, three donor-acceptor (D-A) deep-blue emitters were designed and synthesized via integrating asymmetric quinazoline (PQ) acceptor with weak donating carbazole (Cz) donor. The effect of the position and number of Cz group in PQ unit are investigated, which is also first examples for systematic research about the effect of different position of asymmetric PQ as acceptor on deep OLEDs. Their bandgaps of 3.12∼3.19 eV and the singlet state energy levels of 3.12∼3.19 eV were found to be sufficiently large to achieve deep blue light. As expected, these emitters-based OLEDs exhibit deep blue emission with the maximum wavelength ≤ 450 nm and narrow FWHM ≈ 60 nm. Especially, a CIE of y = 0.080 was achieved for 4PQ-Cz-based OLED. Significantly, the deep blue electroluminescence (EL) spectra of these three emitters-based OLEDs are very stable and the corresponding CIE coordinates deviation (ΔCIE (x, y)) can be negligible under the applied voltage ranging from 5 V to 9 V.     

Tandem Approach to Functionalized Pyrrolo[3,4-α]carbazole-1,3-diones via a Pd-catalyzed Indole-to-carbazole Transformation

A one-pot and efficient tliree-component reaction of indoles, acrylates and maleimides for the synthesis of pyrrolo[3,4-α]carbazole-1,3-dione derivatives was developed. Three C-C bonds and one ring were created in a single step via an indole-to-carbazole transformation triggered by Pd(II)-catalyzed direct C3-alkenylation of indoles.     

含咔唑取代基喹啉铝衍生物的发光性能：一种潜在的多功能荧光传感材料

研究了一种含咔唑取代基喹啉铝(Alq₃)衍生物的发光性能。首先,研究了溶剂对其发光性能的影响。研究发现,在不同溶剂体系中,Alq₃衍生物在发光过程中均存在不同程度的能量传递;但是,溶剂影响Alq₃衍生物的空间结构和电子结构,进而影响能量传递效率,导致激发光谱、发射光谱、荧光效率和荧光寿命均不相同。其中,甲苯起到能量传递桥梁的作用;而DMF在一定程度上阻碍能量传递。与DMF结构类似的DMA作为电子给体加入到Alq₃衍生物溶液中,也起到了类似作用。另外,研究不同金属离子对Alq₃衍生物发光性能的影响发现,Fe3+和Cu2+可引起Alq₃衍生物的荧光猝灭,表明该Alq₃衍生物可以作为多功能荧光传感材料。     

Photophysical and Complexation Properties of Benzenesulfonamide Derivatives with Different Donor and Acceptor Moieties

Pyrrolobenzosulfonamide, indolobenzosulfonamide and carbazolobenzosulfonamide derivatives with different acceptor groups were synthesized and their photophysical properties were compared. The electron donor linking sites are found to influence the emission characteristics of these compounds while acceptor linking sites have no noticeable effects on the spectral properties. P2-A5 which is a C-C linked pyrrole derivative exhibited different spectral properties from the C-N linked pyrrole derivatives. The complexation properties of the molecules were also investigated employing Na (I), Ca (II), Li (I), Mg (II), Zn (II) and Cu (II) ions.     

Synthesis and device properties of carbazole/benzimidazole-based host materials

We report two bipolar host materials bearing hole-transport benzofurocarbazole/indenocarbazole cores and an electron-transport benzimidazole moiety for red phosphorescence organic light emitting devices (PhOLEDs). The two novel host materials exhibited excellent physical properties with high thermal stabilities, appropriate HOMO-LUMO energy levels and balanced charge transport. Both of them were applied to fabricate red PhOLEDs as promising host materials, and 7,7-dimethyl-5-(4′-(1-phenyl-1H-benzo[d]imidazol-2-yl)-[1,1′-biphenyl]-4-yl)-5,7-dihydroindeno[2,1-b]carbazole (ICBI) based device demonstrated outstanding electroluminescence performance with the maximum current efficiency, power efficiency and external quantum efficiency of 33.0 cd/A, 13.9 lm/W and 18.9%, respectively.     

基于咔唑羧酸配体构筑铁基金属有机框架及其对CO2/CH4混合气体的分离性质

通过咔唑羧酸配体(H₃L)与三核铁簇[Fe₃(μ₃-O)(CH₃COO)₆]在水热条件下反应, 合成了具有三维骨架结构的铁基金属有机框架(1). 气体吸附实验结果表明, 化合物1具有高的比表面积且对CO₂的吸附量大于对CH₄的吸附量. 理想溶液吸附理论(IAST)计算结果表明, 化合物1在100 kPa及温度分别为273和298 K下对CO₂/CH₄(体积比为0.5∶0.5)混合气体的分离比分别为3.52和3.15, 预示其可以作为一种CO₂/CH₄分离型材料.