Multi-carbazole derivatives for two-photon absorption data storage: Synthesis, optical properties and theoretical calculation

Two novel quadrupolar organic compounds, 3-(4-((E)-2-(9-butyl-9H-carbazol-6-yl) vinyl)styryl)-9-propyl-9H-carbazole (BCSPC) and 3-(3-(3-((1E)-2-(4-((E)-2-(3-(3,5-bis(9-butyl-9H-carbazol-6-yl)phenyl)-9-butyl-9H-carbazol-6-yl)vinyl)phenyl) vinyl)-9-butyl-9H-carbazol-6-yl)-5-(9-butyl-9H-carbazol-6-yl)phenyl)-9-butyl-9H-carbazole (BCPBC), with different conjugated arms, have been designed and synthesized. Their one- and two-photon absorption (TPA) and excited fluorescence properties have been experimentally investigated. The two-photon absorption cross-sections of two compounds were estimated by two-photon excited fluorescence technique using 200 fs, 76 MHz, Ti:sapphire laser, which are 22 and 154 GM for BCSPC and BCPBC, respectively. The optimal excitation wavelengths are 780 nm for both BCSPC and BCPBC. A data recording experiment proved the potential application of the materials.     

New electron-donating segment to develop thermally activated delayed fluorescence emitters for efficient solution-processed non-doped organic light-emitting diodes

Thermally activated delayed fluorescent(TADF) materials capable of efficient solution-processed nondoped organic light-emitting diodes(OLEDs) are of important and practical significance for further development of OLEDs. In this work, a new electron-donating segment, 2,7-di(9 H-carbazol-9-yl)-9,9-dimethyl-9,10-dihydroacridine(2 Cz-DMAC), was designed to develop solution-processable non-doped TADF emitters. 2 Cz-DMAC can not only simultaneously increase the solubility of compounds and suppress har...     

Direct Amination of Nitroquinoline Derivatives via Nucleophilic Displacement of Aromatic Hydrogen

The vicarious nucleophilic substitution of hydrogen (VNS) reaction in electron-deficient nitroquinolines was studied. Properties of all new products have been characterized by several techniques: MS, HRMS, FTIR, GC-MS, electronic absorption spectroscopy, and multinuclear NMR. The structures of 4-chloro-8-nitroquinoline, 8-(tert-butyl)-2-methyl-5-nitroquinoline, 9-(8-nitroquinolin-7-yl)-9H-carbazole and (Z)-7-(9H-carbazol-9-yl)-8-(hydroxyimino)quinolin-5(8H)-one were determined by single-crystal X-ray diffraction measurements. The 9-(8-nitroquinolin-7-yl)-9H-carbazole and (Z)-7-(9H-carbazol-9-yl)-8-(hydroxyimino)quinolin-5(8H)-one illustrate the nitro/nitroso conversion within VNS reaction. Additionally, 9-(8-isopropyl-2-((8-isopropyl-2-methyl-5-nitroquinolin-6-yl)methyl)-5-nitrosoquinolin-6-yl)-9H-carbazole is presented as a double VNS product. It is postulated that the potassium counterion interacts with the oxygen on the nitro group, which could influence nucleophile attack in that way.     

A facile synthesis of novel benzofuran-2-yl(9-methyl-9H-carbazol-3-yl)methanones

A facile synthesis of hitherto unreported benzofuran-2-yl(9-methyl-9H-carbazol-3-yl)methanones (3a?Cl) is described. The synthesis mainly relies on the ultrasound-assisted Rap?CStoermer reaction of 3-chloroacetyl-9-methyl-9H-carbazole (1) with a variety of salicylaldehydes, as well as 2-hydroxy-1-naphthaldehyde (2) in CH₃CN, with the presence of PEG-400 as a catalyst. This procedure offers easy access to benzofuran-2-yl(carbazolyl)methanone derivatives in a short reaction time and the products are achieved in good yields.     

Synthesis and Properties of Glass-Forming Hydrazones II [1]. Hydrazones Containing Bicarbazolyl Units

 A series of new glass-forming hydrazones containing bicarbazolyl units were synthesized starting from 9-(2-(9H-carbazol-9-yl)-cyclobutyl)-9H-carbazole and 9-(6-(9H-carbazol-9-yl)-hexyl)-9H-carbazole, and their thermal properties were studied. The correlation between their inclination to form glasses and their chemical structures are discussed. The results of a preliminary investigation of the photoelectric properties of amorphous films of the title compounds are briefly reported. The highest hole drift mobility was observed for 9-(2-(9H-carbazol-9-yl)-cyclobutyl)-9H-carbazole-3-carbaldehyde N,N-diphenylhydrazone; at high electric fields, it approaches 1 · 10⁻³ cm²/Vs.     

Synthesis of 2-(9H-carbazol-1-yl)anilines from 2,3′-biindolyl and ketones

Twenty-nine examples of 2-(9H-carbazol-1-yl)anilines were obtained in yields from 27 to 95% by refluxing 2,3′-biindolyl (1 equiv.) and ketones (1 equiv.) in ethanolic HCl. Alkyl, cyclic, and aryl ketones were found to be compatible with this method, however, aldehydes are not. Because the reaction proceeds by addition of the carbonyl C atom to the biindolyl 3-position, this method has high regioselectivity. One example is presented of bridging the two N atoms in the carbazolylaniline product with an acetaldehyde synthon to give a benzodiazepino[lm]carbazole. Also, one example is given of installing a dimethylamino group at the α-position of the starting ketone to give an indolo[3,2-c]carbazole.     

Intramolecular cyclization of 4-amino-3-alkylsulfanyl-1,2,4-triazoles as a method for annelation of thiadiazine and thiadiazole rings

4-Amino-5-(pyridin-4-yl)-4H-1,2,4-triazole-3-thiols reacted with N-substituted isatins to give 2-oxo-3-[5-(pyridin-4-yl)-3-sulfanyl-4H-1,2,4-triazole-4-ylimino]-2,3-dihydro-1H-indoles which were treated with phenacyl bromides to obtain the corresponding S-phenacyl derivatives. The latter underwent base-catalyzed intramolecular cyclization with formation of 6,7-dihydro-5H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazines spiro-fused to 2-oxo-2,3-dihydro-1H-indole fragment at C³. Analogous cyclization of 2,6-di-tert-butyl-4-[5-hetaryl-3-(2-aryl-2-oxoethylsulfanyl)-4H-1,2,4-triazole-4-ylimino]cyclohexa-2,5-dienones involved the imino nitrogen atom to produce the corresponding 6-aroyl-5-(3,5-di-tert-butyl-4-hydroxyphenyl)-3-hetaryl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles.     

Heterocyclizations of 1-(Benzothiazol-2-yl)-4-phenylthiosemicarbazide

1-(Benzothiazol-2-yl)-4-phenylthiosemicarbazide reacted with methyl iodide in the presence of sodium acetate in boiling ethanol to give 2,2′-dithiobis[N-(5-methylsulfanyl-4-phenyl-4H-1,2,4-triazol-3-yl)-benzenamine]. The reaction of the title compound with dimethyl acetylenedicarboxylate in dioxane led to the formation of methyl 3-(benzothiazol-2-yl)-2-(2-methoxy-2-oxoethyl)-2,3-dihydro-1,3,4-thiadiazole-2-carboxylate.     

Synthesis and Properties of Glass-Forming Hydrazones II [1]. Hydrazones Containing Bicarbazolyl Units

Summary.  A series of new glass-forming hydrazones containing bicarbazolyl units were synthesized starting from 9-(2-(9H-carbazol-9-yl)-cyclobutyl)-9H-carbazole and 9-(6-(9H-carbazol-9-yl)-hexyl)-9H-carbazole, and their thermal properties were studied. The correlation between their inclination to form glasses and their chemical structures are discussed. The results of a preliminary investigation of the photoelectric properties of amorphous films of the title compounds are briefly reported. The highest hole drift mobility was observed for 9-(2-(9H-carbazol-9-yl)-cyclobutyl)-9H-carbazole-3-carbaldehyde N,N-diphenylhydrazone; at high electric fields, it approaches 1 · 10⁻³ cm²/Vs. Received September 17, 2001. Accepted (revised) October 16, 2001     

Effects of Substitution Position of Carbazole-Dibenzofuran Based High Triplet Energy Hosts to Device Stability of Blue Phosphorescent Organic Light-Emitting Diodes

High triplet energy hosts were developed through the modification of the substitution position of carbazole units. Two carbazole-dibenzofuran-derived compounds, 9,9′-(dibenzo[b,d]furan-2,6-diyl)bis(9H-carbazole) (26CzDBF) and 4,6-di(9H-carbazol-9-yl)dibenzo[b,d]furan (46CzDBF), were synthesized for achieving high triplet energy hosts. In comparison with the reported hole transport type host, 2,8-di(9H-carbazol-9-yl)dibenzo[b,d]furan (28CzDBF), 26CzDBF and 46CzDBF maintained high triplet energy over 2.95 eV. The device performances of the hosts were evaluated with electron transport type host, 2-phenyl-4, 6-bis(3-(triphenylsilyl)phenyl)-1,3,5-triazine (mSiTrz), to comprise a mixed host system. The deep blue phosphorescent device of 26CzDBF:mSiTrz with [[5-(1,1-dimethylethyl)-3-phenyl-1H-imidazo[4,5-b]pyrazin-1-yl-2(3H)-ylidene]-1,2-phenylene]bis[[6-(1,1-dimethylethyl)-3-phenyl-1H-imidazo[4,5-b]pyrazin-1-yl-2(3H)-ylidene]-1,2-phenylene]iridium (Ir(cb)₃) dopant exhibited high external quantum efficiency of 22.9% with a color coordinate of (0.14, 0.16) and device lifetime of 1400 h at 100 cd m⁻². The device lifetime was extended by 75% compared to the device lifetime of 28CzDBF:mSiTrz (800 h). These results demonstrated that the asymmetric and symmetric substitution of carbazole can make differences in the device performance of the carbazole- and dibenzofuran- derived hosts.     

Synthesis of 1,2,4- and 1,3,4-oxadiazoles from 1-aryl-5-methyl-1<Emphasis Type="Italic">H</Emphasis>-1,2,3-triazole-4-carbonyl chlorides

5-Substituted 2-(1-aryl-5-methyl-1H-1,2,3-triazol-4-yl)-1,3,4-oxadiazoles were synthesized by reaction of 1-aryl-5-methyl-1H-1,2,3-triazole-4-carbonyl chlorides with the corresponding 5-substituted 1H-tetrazoles. 5-Methyl-1-phenyl-1H-1,2,3-triazole-4-carbonyl chloride reacted with N′-hydroxybenzimidamides to give 3-aryl-5-(5-methyl-1-phenyl-1H-1,2,3-triazol-4-yl)-1,2,4-oxadiazoles. Reactions of 4-(5-methyl-1H-1,2,3-triazol-1-yl)benzoic acid with N′-hydroxybenzimidamides resulted in the formation of 3-aryl-5-[4-(5-methyl-1H-1,2,3-triazol-1-yl)phenyl]-1,2,4-oxadiazoles.     

Intramolecular amidation: synthesis of novel imidazo[2,1-b][1,3,4]thiadiazole and imidazo[2,1-b][1,3]thiazole fused diazepinones

Novel heterocyclic systems 2-alkyl/aryl-9-(2-hydroxybenzylidene)-7,9-dihydro-8H-[1,3,4]thiadiazolo[2′,3′:2,3]imidazo[4,5-d][1,2]diazepin-8-one and 9-(2-hydroxy-benzylidene)-3,3-dimethyl-3,4,7,9-tetrahydro-2H-11-thia-4b,6,7,10-tetraazaindeno[1,2-a]azulene-1,8-dione are synthesized via an intramolecular amidation reaction. An interesting ring opening and cyclization of 2-alkyl/aryl-6-(2-oxo-2H-chromen-3-yl)imidazo[2,1-b][1,3,4]thiadiazole-5-carbaldehyde and 6,6-dimethyl-8-oxo-2-(2-oxo-2H-chromen-3-yl)-5,6,7,8-tetrahydroimidazo[2,1-b][1,3]benzothiazole-3-carbaldehyde are discussed.     

Synthesis and Bioinformatic Characterization of New Schiff Bases with Possible Applicability in Brain Disorders

(1) Background: The research aims to find new treatments for neurodegenerative diseases, in particular, Alzheimer’s disease. (2) Methods: This article presents a bioinformatics and pathology study of new Schiff bases, (EZ)-N′-benzylidene-(2RS)-2-(6-chloro-9H-carbazol-2-yl)propanehydrazide derivatives, and aims to evaluate the drug-like, pharmacokinetic, pharmacodynamic and pharmacogenomic properties, as well as to predict the binding to therapeutic targets by applying bioinformatics, cheminformatics and computational pharmacological methods. (3) Results: We obtained these Schiff bases by condensing (2RS)-2-(6-chloro-9H-carbazol-2-yl)propanehydrazide with aromatic aldehydes, using the advantages of microwave irradiation. The newly synthesized compounds were characterized spectrally, using FT-IR and NMR spectroscopy, which confirmed their structure. Using bioinformatics tools, we noticed that all new compounds are drug-likeness features and may be proposed as potentially neuropsychiatric drugs (4) Conclusions: Using bioinformatics tools, we determined that the new compound 1e had a high potential to be used as a good candidate in neurodegenerative disorders treatment.     

Design and synthesis of novel quinoline derivatives bearing oxadiazole,isoxazoline, triazolothiadiazole,triazolothiadiazine, and piperazine moieties

A new series of 2,3-disubstituted quinoline derivatives were synthesized from 2-chloroquinoline-3-carbaldehyde. In the reaction sequence, acetanilide was cyclized to give 2-chloroquinoline-3-carbaldehyde 1 , which was transformed to 2-(4-phenylpiperazin-1-yl)quinolin-3-carbaldehyde 2 by reaction with 4-phenylpiperazine in DMF-containing anhydrous K₂CO₃; then, compound 2 was oxidized by iodine in methanol, and methyl 2-(4-phenylpiperazin-1-yl)quinoline-3-carboxylate 3 was synthesized. The key intermediate 4 , 4-amino-5-[2-(4-phenylpiperazin-1-yl)quinolin-3-yl]-4H-1,2,4-triazole-3-thiol, was prepared using the ester 3 by a series of step. Reaction of 5 with various aromatic carboxylic acids or phenacyl bromides yielded 1,2,4-triazolo[3,4-b][1,3,4]thiadiazoles 5a-c and 1,2,4-triazolo[3,4-b][1,3,4]thiadiazines 6a-c , respectively. Moreover, compound 2 condensed with o-phenylenediamine to give 2-[2-(4-phenylpiperazin-1-yl)quinolin-3-yl]-1H-benzimidazole 7 . Interaction of 7 and 2-chloromethyl-5-aryl-1,3,4-oxadiazoles in the presence of K₂CO₃ led to the title compounds 8a-c . Furthermore, 4,5-dihydroisoxazoline derivatives 9a-c were obtained by the reaction of readily accessible starting materials including 2-(4-phenylpiperazin-1-yl)quinolin-3-carbaldehyde 2 , 1-phenyl-2-(triphenylphosphoranylidene)ethanone and hydroximoyl chlorides under mild conditions in the presence of Et₃N. The hydrazone intermediates 10a-c were obtained by the condensation of 2 with aroylhydrazides in ethanol, then, refluxing in acetic anhydride yielded 3-acetyl-5-aryl-2-[2-(4-phenylpiperazin-1-yl)quinolin-3-yl]-2,3-dihydro-1,3,4-oxadiazoles 11a-c . Structures of these compounds were established by their elemental analysis, IR, ¹H NMR, and mass spectral data.     

Fused polycyclic nitrogen-containing heterocycles: IX. Synthesis and molecular structure of methyl 3-(2-R-5-phenylthiazol-4-yl)-7-phenyl-7<Emphasis Type="Italic">H</Emphasis>-[1,2,4]triazolo-[3,4-<Emphasis Type="Italic">b</Emphasis>][1,3,4]thiadiazine-6-carboxylates

4-Amino-3-(2-R-5-phenylthiazol-4-yl)-1,2,4-triazole-5-thiones react with methyl 3-chloro-2-oxo-3-phenylpropionate to give methyl 3-(2-R-5-phenylthiazol-4-yl)-7-phenyl-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazine-6-carboxylates. According to the X-ray diffraction data, the thiazole ring in the products is planar, while the thiadiazine ring has a distorted unsymmetrical boat conformation. Depending on the substituent in the thiazole ring, methyl 3-(2-R-5-phenylthiazol-4-yl)-7-phenyl-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazine-6-carboxylates in crystal give rise to different supramolecular structures, lamellar and cylindrical.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 9, 2004, pp. 1358–1365.Original Russian Text Copyright © 2004 by Mamedov, Mustakimova, Gubaidullin, Litvinov, Levin.     

Features of the reaction of 4-bromobut-2-enylphosphonium salts with monosubstituted hydrazines

(4-Bromobut-2-en-1-yl)triphenylphosphonium bromide reacted with phenylhydrazine at 2°C in the presence of sodium carbonate to form triphenyl[4-(2-phenylhydrazinylidene)but-2-en-1-yl]phosphonium bromide in 62% yield. The obtained N-phenylhydrazine derivatives cyclized into the corresponding pyrazoline derivatives of phosphonium salts. Unlike phenylhydrazine, ethylhydrazine reacted with (4-bromobut-2-ene-1-yl)triphenylphosphonium bromide under the same conditions to afford triphenyl[(1-ethyl-4,5-dihydro-1Hpyrazol-3-yl)methyl]- and -[(1-ethyl-1H-pyrazol-3-yl)methyl]phosphonium bromides in yields of 60 and 40%.     

一种含咔唑基团的混配型钌(II)配合物的合成、表征和酸碱性质研究

合成了钌(II)配合物cis-[Ru(HL)(Hdcbpy)(NCS)₂]^－•[N(C₄H₉)₄]^＋ (HL＝2-(9-乙基-9H-3-咔唑基)-1H-咪唑[4,5-f] [1,10]邻菲啰啉, H₂dcbpy＝4,4'-二羧酸-2,2'-联吡啶). 采用元素分析、核磁共振氢谱、红外光谱、紫外-可见吸收光谱、质谱(MS)对配合物进行了表征. 通过紫外-可见吸收光谱和稳态荧光光谱, 研究了该配合物的基态和激发态酸碱性质. 结果表明该配合物在基态时能发生5步质子化/去质子化反应, 表现出基于光致发光强度和激发态能量转移途径的质子化/去质子化诱导的分子开关性质.     

Synthesis and electronic spectra of new low-molecular weight compounds with possible application in electroluminescent layers

Two new low-molecular weight compounds — (Z)-4-(4-(dimethylamino)benzylidene)-1-(9-ethyl-9H-carbazol-3-yl)-2-phenyl-1H-imidazol-5(4H)-one and 2-(6-hydroxyhexyl)-6-(pyrrolidin-1-yl)-1H-benzo[de]isoquinoline-1,3(2H)-dione) — with possible application in organic light-emitting devices were synthesized. Their photophysical properties in solution and in polymer films were investigated. The determined relative fluorescence quantum yields in solution for both compounds were 0.003 and 0.51, while those in poly(methyl methacrylate) films were around 0.10 and 1.0, respectively. For 1H-imidazol-5(4H)-one derivative, single-layer organic displays with one emitting layer were prepared by spin-coating technology. The applied voltage was 40 V (AC) with 1–3 KHz frequency. The emission maximum of the experimental AC display structures was at 600–630 nm. For displays with 2-(6-hydroxyhexyl)-6-(pyrrolidin-1-yl)-1H-benzo[de]isoquinoline-1,3(2H)-dione) the applied voltage was 60 V (AC) with 6-9 KHz frequency, but its future success will require more appropriate binding polymers. Based on the obtained experimental results, it is concluded that the investigated compounds could be applied for preparation of color electroluminescent structures.      

Practical and efficient synthesis of the (R)-atropisomer of a 4-phenyl 1,2,4-triazole derivative as a selective GlyT1 inhibitor

Herein we describe a novel and efficient method for synthesizing the (R)-atropisomer of 3-[3-ethyl-5-(6-phenylpyridin-3-yl)-4H-1,2,4-triazol-4-yl]-2-methylbenzonitrile 1, a novel GlyT1 inhibitor. The diastereomeric salt formation of 3-[3-ethyl-5-(6-phenylpyridin-3-yl)-4H-1,2,4-triazol-4-yl]-2-methylbenzoic acid 7 with (1R,2S)-(?)-2-amino-1,2-diphenylethanol afforded the desired (R)-atropisomer. We also report the determination of the absolute configuration of (R)-7 by powder X-ray diffraction.     

Reactions of 9-alkyl-3-aminocarbazoles with ethyl-3-oxo-butanoate and identification of the products obtained

The reactions in benzene of 9-alkyl-3-aminocarbazoles with ethyl-3-oxobutanoate yielded ethyl-3-[(9-alkyl-9H-carbazol-3-yl)amino]but-2-enoate condensation products or N-(9-ethyl-9H-carbazol-3-yl)-3-oxobutanamide acylation products. The condensation products were cyclized to the corresponding 4,7-dihydro-pyrido[2,3-c]-carbazol-1-ones upon heating in mineral oil at 240-250 degrees C. The structures of the synthesized compounds were investigated by IR, mass spectrometry, (1)H- and (13)C-NMR spectroscopy and MM2 molecular mechanics and AM1 semi-empirical quantum mechanical methods.