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51.
In this paper,we report a novel approach to the heteroaryl-condensed nuclei of natural furo[3,2-a]carbazole alkaloids.Our synthetic studies use N-phthaloyl tryptophan methyl ester as starting material and zinc ion mediated transamination reaction as the key step.This work also implicated a novel strategy to assemble other [a]-fused carbazoles. 相似文献
52.
《Acta Crystallographica. Section C, Structural Chemistry》2017,73(4):319-324
Nucleophilic substitution of F atoms in 5,6‐difluorobenzo[c ][1,2,5]thiadiazole (DFBT) for carbazole could be potentially interesting as a novel way of synthesizing building blocks for new conjugated materials for applications in organic chemistry. The crystal structures of 5,6‐bis(9H‐carbazol‐9‐yl)benzo[c ][1,2,5]thiadiazole (DCBT), C30H18N4S, and its hydrate, C30H18N4S·0.125H2O, were investigated using single‐crystal X‐ray analysis. The hydrate contains two symmetry‐independent DCBT molecules. The dihedral angles between the plane of the central benzothiadiazole fragment and that of the carbazole units vary between 50.8 and 69.9°, indicating conformational flexibility of the DCBT molecule in the crystals, which is consistent with quantum chemical calculations. The analysis of the crystal packing of DCBT revealed that the experimental triclinic structure could be described as a distortion from a hypothetical higher‐symmetry monoclinic structure. The quantum chemical calculations of two possible monoclinic structures, which are related to the experimental structure by a shifting of molecular layers, showed that the proposed structures are higher in energy by 5.4 and 10.1 kcal mol−1. This energy increase is caused by less dense crystal packings of the symmetric structures, which results in a decrease of the number of intermolecular interactions. 相似文献
53.
以双(2?氯乙基)氨基甲酸叔丁酯、2,2?(乙烷?1,2?二丁基(氧基))二乙硫醇和N?乙基咔唑为起始原料,设计、合成了一种含有杂冠醚基团的新型荧光探针分子L,其结构经1H NMR、13C NMR及高分辨质谱进行了表征。随后利用荧光光谱在水/乙醇溶剂(4∶1,V/V)中研究了探针L对Ag+的选择性识别。研究结果表明,探针L与Ag+以1∶1的比例配位。通过计算得到配位常数Ka为2.01×105 L·mol-1,检测限为4.13μmol·L-1。通过实验证明,该探针分子可应用于河流等环境水样中Ag+的检测。 相似文献
54.
Kim J Yun MH Anant P Cho S Jacob J Kim JY Yang C 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(51):14681-14688
On the basis of theoretical considerations of the intramolecular charge transfer (ICT) effect, we have designed a series of donor (D)–acceptor (A) conjugated polymers based on bis‐benzothiadiazole (BBT). A PPP‐type copolymer of electron‐rich 2,7‐carbazole (CZ) and electron‐deficient BBT units poly[N‐(2‐decyltetradecyl)‐2,7‐carbazole‐co‐7,7′‐{4,4′‐bis‐(2,1,3‐benzothiadiazole)}] ( PCZ‐BBT ), a PPV‐type copolymer poly[N‐(2‐decyltetradecyl)‐2,7‐carbazolevinylene‐co‐7,7′‐{4,4′‐bis‐(2,1,3‐benzothiadiazolevinylene)}] ( PCZV‐BBTV ), and a tercopolymer based on carbazole, thiophene, and BBT poly[N‐(2‐decyltetradecyl)‐2,7‐(di‐2‐thienyl)carbazole‐co‐7,7′‐{4,4′‐bis‐(2,1,3‐benzothiadiazole)}] ( PDTCZ‐BBT ) have been synthesized to understand the influence of BBT acceptor structure and linkage on the photovoltaic characteristics of the resulting materials. Both the HOMO and LUMO of the resulting polymers are found to be deeper‐lying than those of benzothiadiazole‐based polymers. The measured electrochemical band gaps (eV) are in the following order: PDTCZ‐BBT (1.65 eV) < PCZV‐BBTV (1.69 eV) < PCZ‐BBT (1.75 eV). All the polymers provide a photovoltaic response when blended with a fullerene derivative as an electron acceptor. The best cell reaches a power conversion efficiency of 2.07 % estimated under standard solar light conditions (AM1.5G, 100 mW cm?2). We demonstrate for the first time that BBT‐based polymers are promising materials for use in bulk‐heterojunction solar cells. 相似文献
55.
L. G. Samsonova N. S. Eremina V. A. Svetlichnyi T. N. Kopylova G. V. Maier N. S. Kobotaeva E. E. Sirotkina 《Journal of Applied Spectroscopy》2006,73(2):194-199
We have studied the spectral and lasing properties of 4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM)
in polyepoxypropylcarbazole (PEPK), polybutylcarbazole (PBK), and polyvinylcarbazole (PVK) films when excited by emission
from a XeCl laser (λ = 308 nm) and the second harmonic of a YAGNd laser (λ = 532 nm). Stimulated emission was excited without
an external cavity in the traveling wave mode in films of thickness 0.5–0.8 μm, obtained by the centrifuging method.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 2, pp. 177–181, March–April, 2006. 相似文献
56.
Abdiaziz A. Farah William J. Pietro 《Journal of polymer science. Part A, Polymer chemistry》2005,43(23):6057-6072
A series of poly(N‐(ω′‐alkylcarbazoly) methacrylates) tris(bipyridine) Ru‐centered bifunctional polymers with good filming, thermal, and solubility properties were synthesized and characterized. Atom transfer radical polymerization (ATRP) of N‐(ω′‐alkylcarbazoly) methacrylates in solution was used, where Ru complexes with one and three initiating sites acted as metalloinitiators with NiBr2(PPh3)2 as a catalyst. ATRP reaction conditions with respect to polymer molecular weights and polydispersity indices (PDI) of the target bifunctional polymers were examined. Electronic absorption and emission spectra of the resultant functional polymers provided evidence of chromophore presence within a single polymeric chain. The thermal properties of all polymers were also investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), and these analyses have indicated that these polymers possess higher thermal stabilities than poly(methyl methacrylate) (PMMA) obtained via free radical polymerization. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6057–6072, 2005 相似文献
57.
Weihua Tang Tingting Lin Lin Ke Zhi‐kuan Chen 《Journal of polymer science. Part A, Polymer chemistry》2008,46(23):7725-7738
2,7‐dibromo‐N‐hexylcarbazole is successfully synthesized in three steps with an overall 37% yield. Novel 2,7‐carbazole‐based sterically hindered conjugated polymers are further synthesized. In the backbone structure of polymer P1 , alkylated bithiophene moiety is β‐substituted with dodecyl chains on both thiophene rings, adopting the tail‐to‐tail configuration. While for polymers P2 and P3 , partially planarized thieno[3,2‐b]thiophene moiety ( P2 ) and β‐pentyl substituted thieno[3,2‐b]thiophene ( P3 ) are incorporated. All polymers demonstrate efficient blue‐to‐green light emission, good thermal stability (Td ≥ 379 °C), and high glass transition temperatures (Tg = 118 °C). The optical and electronic properties of the resulted polymers are tuned by the incorporated alkyl chains. For instance, the incorporation of β‐pentyl group in thieno[3,2‐b]thiophene moiety endows P3 with blue‐shifted photophysical spectra, reduced fluorescence quantum yield and larger band gap in comparison with P2 . The steric effect of incorporated alkyl chains is further illustrated by geometry optimization of three model oligomers (analogues to the repetition units of P1–P3 ) using density functional theory. Sterically hindered polymers P1 and P2 exhibit high charge transport ability and moderate electroluminescent properties in primarily tested single‐layer light‐emitting diodes (configuration: ITO/PEDOT:PSS/Polymer/Ca/Ag). © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7725–7738, 2008 相似文献
58.
59.
Back Cover: Covalent Modification of Graphene Oxide with Carbazole Groups for Laser Protection (Chem. Eur. J. 12/2015) 下载免费PDF全文
60.
Yuanyuan Cui Yaoyang Meng Yun Hu Yuqi Chen Yixian Yang Min Fang Cun Li Weiju Zhu 《中国化学会会志》2023,70(1):68-75
A novel fluorescent probe, LCH , based on dicyanisophorone and carbazole, was prepared for the visual detection of Cu2+. The probe LCH could recognize Cu2+ by fluorescence quenching in EtOH/H2O (1/4, v/v) solution, which could be easily identified under the 365 nm UV lamp, and the detection limit was as low as 0.785 μM. The recognition mechanism of probe LCH with Cu2+ was determined by combining 1H NMR titration, MS, and theoretical calculations. Practical application experiments showed that probe LCH could be used to detect Cu2+ in the test strip experiments. Cell imaging experiments showed that the probe LCH owned good cell permeability and could be applied to the imaging of Cu2+ in HepG2 cells. In addition, fluorescence colocalization experiments showed that LCH could target lipid droplets. These results indicate that the probe LCH will have a good application prospect in environmental detection and clinical medicine. 相似文献