Facile Procedure for the Synthesis of 3-Acetyl-9-ethylcarbazole and Corresponding Functionalized Bis-β-diketone Compounds

Acetylation-substituted N-ethylcarbazole at the 3-position was synthesized in 80% yield using ZnCl₂ as catalyst, and its corresponding functionalized bis-β-diketone compounds 2a and 2b were prepared by Claisen condensation with acceptable yields. Lanthanide complexes with the two compounds could be used as potential luminescent materials.     

Bis-amidopyrrolyl receptors based on anthracene and carbazole

A new set of diamide receptors containing anthracene and carbazole bridging subunits and either pyrrole or phenyl substituents were synthesised. The four systems produced in this way were shown to bind representative anions in DMSO-d ₆ solution and in the solid state. A higher relative affinity for two test oxoanions, namely dihydrogen phosphate and benzoate, over chloride anion was seen in solution, with the anions in question being studied in the form of their respective tetrabutylammonium salts. However, the specifics of the anion recognition process were seen to depend on structure, with the pyrrole-containing systems displaying higher relative affinities than their corresponding phenyl-containing congeners, and the carbazole receptors proving more effective than the anthracene analogues. Such observations provide support for the notion that both the carbazole NH and the pyrrolic NH protons play an important role in stabilising the receptor-bound anions in solution. Structural analyses of several anion complexes of the diamidopyrrole carbazole receptor reveal that this is not necessarily the case in the solid state; specifically, the pyrrole NH protons are seen to interact with the amide oxygen of another molecule. The net result is an extended one-dimensional coordination polymer.     

以咔唑为给体的分子内电荷转移化合物的自组装及发光性质

设计合成了两种以咔唑为给体单元,苯并噻二唑为受体单元的分子内电荷转移化合物((E)-4-((4-(4-(9H-咔唑-9-基)苯乙烯基)苯基)乙炔基)-7-溴苯[c][1,2,5]噻二唑(CzPB-Br)和4,7-双((4-((E)-4-(9H-咔唑-9-基)苯乙烯基)苯基)乙炔基)苯[c][1,2,5]噻二唑(CzPBPCz))。 研究了紫外、荧光等光物理性质,发现CzPB-Br和CzPBPCz的溶液态在可见区域404和442 nm有明显特征紫外可见吸收峰,同时在557和588 nm处有明显的荧光发射。 结合理论计算考察了共轭长度对两种化合物性能的影响。 两个化合物利用给-受分子间的偶极-偶极、π-π等相互作用,通过良溶剂向不良溶剂扩散和热饱和溶液析出的自组装方法,分别获得了一维微米线、多边形微米片等聚集态结构。 其中,一维的微米线宽度为1~2 μm,长度可达100 μm以上。 一维微米线和多边形微米片分别在515和568 nm处显示出了较强的发光,同时还显示出了光波导的特征,为获得高性能低维有机光电纳米材料提供了新思路。     

Electrochemically Induced Synthesis of Poly(2,6‐carbazole)

The formation of a poly(2,6‐carbazole) derivative during an electrochemical polymerization process is shown. Comparison of 3,5‐bis(9‐octyl‐9H‐carbazol‐2‐yl)pyridine and 3,5‐bis(9‐octyl‐9H‐carbazol‐3‐yl)pyridine by electrochemical and UV–Vis‐NIR spectroelectrochemical measurements and DFT (density functional theory) calculation prove the formation of a poly(2,6‐carbazole) derivative. Both of the compounds form stable and electroactive conjugated polymers.

     

Syntheses and Crystal Structures of 9-Ethyl-1,3,6,8-tetra-aryl-9H-carbazole Compounds

The title compounds 9-ethyl-1,3,6,8-tetra-p-tolyl-9H-carbazole (1) and 9-ethyl-1,3,6,8-tetrakis-(4-fluoro-phenyl)-9H-carbazole (2) were synthesized and characterized by single-crystal X-ray diffraction. Thereinto, the crystal structures of compounds 1 and 2 were composed by asymmetry units. The ratio of compounds 1 and 2 to the solvent molecule cyclohexane (CYH) is 4/3. X-ray analysis reveals that the 1,3,6,8-phenyl groups are distorted at large angles relative to the planar carbazole ring. Furthermore, the luminescent and thermal properties of 1 and 2 have also been investigated. It can be seen that thermal stability of compound 1 with p-tolyl is better than that of 2 with 4-fluoro-phenyl. Fluorescence spectra analysis showed that compounds 1 and 2 have strong UV emission.     

Synthesis, Crystal Structure and Theoretical Studies of (E)-1-((9-(2-(2-methoxyethoxy)ethyl)-9H-carbazol-3-yl)methylene)thiosemicarbazide

A novel thiosemicarbazide derivative, (E)-1-(9-(2-(2-methoxyethoxy)ethyl)-9H-carbazol-3-yl) methylene)-thiosemicarbazide (CMT), was synthesized and structurally characterized by IR, 1H-NMR, EI-MS and single-crystal X-ray diffraction. It crystallizes in monoclinic, space group P21/c with a = 14.769(5), b = 8.279(5), c = 17.166(5) , β = 114.391(5)°, V = 1911.6(14) 3, Z = 4, F(000) = 784, Dc = 1.287 g/m3, Mr = 370.47, μ = 0.190 mm-1, the final R = 0.0390 and wR = 0.1358 for 1446 observed reflections with Ⅰ > 2σ(Ⅰ). The UV-vis absorption spectra of CMT were explained based on quantum chemical calculations, using time dependent density functional theory (TD-DFT) at the B3LYP/6-31G (d) level.     

Controlled helical orientation of carbazole in amino acid derived poly(N‐propargylamide)s

Novel L ‐alanine and L ‐glutamic acid derivatized, carbazole‐containing N‐propargylamides [N‐(9‐carbazolyl)ethyloxycarbonyl‐L ‐alanine N′‐propargylamide and N‐(9‐carbazolyl)ethyloxycarbonyl‐L ‐glutamic acid‐γ‐benzyl ester N′‐propargylamide] were synthesized and polymerized with (nbd)Rh⁺[η⁶‐C₆H₅B^?(C₆H₅)₃] (nbd = norbornadiene) as a catalyst to obtain the corresponding polymers with moderate molecular weights in high yields. Polarimetry, circular dichroism, and ultraviolet–visible spectroscopy studies revealed that both poly[N‐(9‐carbazolyl)ethyloxycarbonyl‐L ‐alanine N′‐propargylamide] and poly[N‐(9‐carbazolyl)ethyloxycarbonyl‐L ‐glutamic acid‐γ‐benzyl ester N′‐propargylamide] took a helical structure with a predominantly one‐handed screw sense in tetrahydrofuran, CHCl₃, and CH₂Cl₂. The helix content of poly[N‐(9‐carbazolyl)ethyloxycarbonyl‐L ‐alanine N′‐propargylamide] could be tuned by heat or the addition of a protic solvent, and the helical sense of poly[N‐(9‐carbazolyl) ethyloxycarbonyl‐L ‐glutamic acid‐γ‐benzyl ester N′‐propargylamide] was inverted by heat in CHCl₃ or in mixtures of tetrahydrofuran and CH₂Cl₂. Poly[N‐(9‐carbazolyl) ethyloxycarbonyl‐L ‐alanine N′‐propargylamide] and poly[N‐(9‐carbazolyl)ethyloxycarbonyl‐L ‐glutamic acid‐γ‐benzyl ester N′‐propargylamide] also took a helical structure in film states. They showed small fluorescence in comparison with the monomers and redox activity based on carbazole. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 253–261, 2007     

Preparation and Characterization of Fullerene C_(60) and Phthalocyanine Co-grafted Poly(epoxy propyl carbazole)

Fullerenes and its derivatives have attracted great interest from the viewpoints of both fundamental science and potential application. Fullerene-doping polymeric photoconductors have been extensively investigated due to their potential technological application. The enhancement of the photoconductivity of the poly (N-vinylcarbazole) (PVK) films by dopong with fullerenes (a mixture of C60 and C70) was for the first time reported by Wang1. He proposed that enhanced photoconductivity was attr…     

Exploring 9‐arylcarbazole moiety as the building block for the synthesis of photoluminescent group 10–12 heavy metal diynes and polyynes with high‐energy triplet states

A new series of organic‐soluble and thermally stable group 10 platinum(II) polyyne polymers functionalized with 9‐arylcarbazole moiety trans‐[? Pt(PBu₃)₂C?CRC?C? ]_n (R = 9‐arylcarbazole‐3,6‐diyl; aryl = phenyl, p‐methylphenyl, p‐fluorophenyl) were prepared in good yields by Hagihara's dehydrohalogenative polymerization of trans‐[PtCl₂(PBu₃)₂] with HC?CRC?CH under ambient conditions. The regiochemical structures of the polymers were characterized by multinuclear NMR spectroscopy. We discuss the optical spectroscopy of these polymetallaynes and compare the results with their bimetallic molecular model complexes trans‐[Pt(Ph)(PEt₃)₂C?CRC?CPt(Ph)(PEt₃)₂] as well as its group 11 gold(I) and group 12 mercury(II) congeners [(PPh₃)AuC?CRC?CAu(PPh₃)] and [MeHgC?CRC?CHgMe]. The structural properties of several model complexes were studied by X‐ray crystallography. The influence of the heavy metal atom and the 9‐aryl substituent of carbazole on the phosphorescence behavior and the spatial distribution of the lowest singlet (S₁) and triplet (T₁) excitons in these metalated alkynyl systems are comprehensively elucidated. The present work indicates that the efficiency of organic triplet emissions harnessed through the heavy‐atom effect of group 10–12 transition metals in the main chain generally follows the order Pt > Au > Hg but the optical properties of the materials are relatively insensitive to the nature of the 9‐aryl group on the carbazolyl ring. All of these metallaynyl‐carbazole materials with high‐energy T₁ states of 2.68 eV or higher show high phosphorescence efficiencies at low temperatures. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5588–5607, 2006     

Synthesis of carbazole-linked cyclic and acyclic peptoids with antibacterial activity

This paper describes the synthesis of several novel cyclic and acyclic peptoids, the former structurally comprising a tripeptide moiety linked through a carbazole scaffold. In a key step, a ring-closing metathesis reaction was used giving efficient access to this new class of cyclic peptoids. The target compounds were tested against Staphylococcus aureus (ATCC 6538P) and their minimum inhibitory concentration (MIC) values were determined. These compounds showed moderate to poor activities with MIC values ranging from 15-250 μg/mL.