57103-01-2Relevant articles and documents
Development of colloidally stable carbazole-based fluorescent nanoaggregates
Svechkarev, Denis,Kyrychenko, Alexander,Payne, William M.,Mohs, Aaron M.
, p. 55 - 64 (2018)
Fluorescent nanomaterials require high colloidal stability for effective use in imaging and sensing applications. We herein report the synthesis of carbazole-based organic fluorescent nanoaggregates, and demonstrate the superior colloidal stability of alkyl-substituted dye aggregates over their non-alkylated analogs. The role of alkyl chains in self-assembly and stability of such nanoaggregates is discussed based on both experimental and molecular dynamics simulation data, and spectral characteristics of the precursor dyes and their aggregates are described. The obtained results provide new insights on development of colloidally stable organic fluorescent nanomaterials with low polydispersity.
Pyridazine–carbazole based fluorescent probes for volatile acid detection
Han, Won-Sik,Kim, Seung-Hwan,Lee, Sohee,Lee, Sunhee,Lee, Yeeun,Lee, Yong Sup,Wang, Kang-Kyun,Yang, Kwang-Hwan
, (2021)
Stimuli-responsive materials based on donor–acceptor systems have great potential for sensing applications, including in the solid state. Herein, two push–pull-type molecules, 3,6-di(9H-carbazol-9-yl)pyridazine (CzPyr–H) and 3,6-bis(3,6-dimethoxy-9H-carbazol-9-yl)pyridazine (CzPyr–OMe), each of which contain two carbazole donors and a pyridazine acceptor, were designed and synthesized. The photophysical properties of CzPyr–H and CzPyr–OMe were systematically explored with the aim of switching the absorption and emission properties using trifluoroacetic acid (TFA) as an external analyte, thus realizing volatile acid sensing. The protonation of the central pyridazine unit led to a broad absorption band at longer wavelengths owing to intramolecular charge transfer (ICT), and the emission intensity gradually decreased with increasing TFA concentration. Density functional theory calculations of the HOMO–LUMO energy gaps and orbital distributions of CzPyr–H and CzPyr–OMe as well as their protonated forms, CzPyr–H(H+) and CzPyr–OMe(H+), confirmed that charge transfer occurred in the protonated species. In their aggregated solid states, both compounds showed interesting emission properties including aggregation-enhanced emission (AEE). Utilizing their TFA sensitivity and the AEE phenomenon, CzPyr–H and CzPyr–OMe were successfully applied as fluorescent probes for volatile acid detection and as security ink for information encryption on paper.
Enhancement of redox stability and electrochromic performance of aromatic polyamides by incorporation of (3,6-dimethoxycarbazol-9-yl)-triphenylamine units
Wang, Hui-Min,Hsiao, Sheng-Huei
, p. 272 - 286 (2014)
New series aromatic polyamides with (carbazol-9-yl)triphenylamine units were synthesized from a newly synthesized diamine monomer, 4,4′-diamino- 4″-(3,6-dimethoxycarbazol-9-yl) triphenylamine, and aromatic dicarboxylic acids via the phosphorylation polyamidation technique. These polyamides exhibit good solubility in many organic solvents and can be solution-cast into flexible and strong films with high thermal stability. They show well-defined and reversible redox couples during oxidative scanning, with a strong color change from colorless neutral form to yellowish green and blue oxidized forms at applied potentials scanning from 0.0 to 1.3 V. They show enhanced redox-stability and electrochromic performance as compared to the corresponding analogs without methoxy substituents on the active sites of the carbazole unit. Copyright
A star-shaped cyclopentadithiophene-based dopant-free hole-transport material for high-performance perovskite solar cells
Lee, Kun-Mu,Yang, Jui-Yu,Lai, Ping-Sheng,Luo, Ke-Jyun,Yang, Ting-Yu,Liau, Kang-Ling,Abate, Seid Yimer,Lin, Yan-Duo
, p. 6444 - 6447 (2021/07/02)
A new cyclopentadithiophene (CPDT)-based organic small molecule serves as an efficient dopant-free hole transport material (HTM) for perovskite solar cells (PSCs). Upon incorporation of two carbazole groups, the resulting CPDT-based HTM (C-CPDT) shows an impressive power conversion efficiency (PCE) of 19.68% with better stability compared with those of spiro-OMeTAD.
A simple strategy to achieve efficient thermally activated delayed fluorescent emitters via enhancing electron donating ability of donors
Li, Ganggang,Li, Jiafang,Li, Kai,Liu, He,Liu, Zhiwen,Wang, Zhiming,Yang, Chuluo,Zhan, Qun,Zhang, Bing,Zhou, Changjiang
, (2020/05/18)
Simultaneously achieving both effective reverse intersystem crossing (RISC) process and high values of radiative decay rate (kr)/photoluminescent quantum yield (PLQY) are critical for efficient thermally activated delayed fluorescent (TADF) emitters. The separation of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) through typical molecular geometry tuning method guarantees a small ΔEST but results in disfavored oscillator strength for fluorescent decay. Herein, a simple method is provided to facilitate the reverse intersystem crossing (RISC) of TADF emitters via enhancing electron donating property of donors rather than twisting the donor-acceptor configuration. Three molecules, namely Me-Cz, Me-MOC and Me-DOC, are designed and synthesized. The introduction of methoxy group enhances the electron-donating ability of carbazole. The stabilized charge transfer state features a reduced splitting energy between the first singlet and triplet excited state, thus activating TADF process. Consequently, the molecules Me-DOC and Me-MOC achieve good external quantum efficiency of 18.6% and 12.4% in electroluminescent devices.
One-pot synthesis of a white-light emissive bichromophore operated by aggregation-induced dual emission (AIDE) and partial energy transfer
Biesen, Lukas,Deni?en, Melanie,Hannen, Ricarda,Hoffmann, Katrin,Itskalov, Dana,Müller, Thomas J. J.,Nirmalananthan-Budau, Nithiya,Reiss, Guido J.,Resch-Genger, Ute
supporting information, p. 7407 - 7410 (2020/07/15)
Merocyanine-triarylamine bichromophores are readily synthesized by sequentially Pd-catalyzed insertion-alkynylation-Michael-Suzuki four-component reactions. White-light emissive systems form upon aggregation in 1 : 99 and 0.1 : 99.9 vol percent CH2Cl2-cyclohexane mixtures, ascribed to aggregation-induced dual emission (AIDE) in combination with partial energy transfer between both chromophore units as supported by spectroscopic studies.
Methoxy- and tert-butyl-substituted meta-bis(N-carbazolyl)phenylenes as hosts for organic light-emitting diodes
Keruckas, Jonas,Volyniuk, Dmytro,Simokaitiene, Jurate,Narbutaitis, Edgaras,Lazauskas, Algirdas,Lee, Pei-Hsi,Chiu, Tien-Lung,Lin, Chi-Feng,Arsenyan, Pavel,Lee, Jiun-Haw,Grazulevicius, Juozas V.
, p. 317 - 326 (2019/07/02)
Two new analogues of a popular host material, meta-bis(N-carbazolyl)phenylene (mCP), bearing either methoxy- (mCP-OMe) or tert-butyl (mCP-t-Bu) substituents at C-3 and C-6 positions of carbazole moieties were synthesized and characterized. These materials exhibit higher glass-transition temperatures (79 and 145 °C) than mCP (67 °C). They show reversibility upon electrochemical oxidation while preserving high enough triplet energy levels (2.86 and 2.97 eV). The vacuum-deposited layer of mCP-t-Bu showed hole mobility of 8 × 10?3 cm2V?1s?1 at the electric field of 1.2 × 105 Vcm?1. This value is more than by one order of magnitude higher than that of mCP. The new compounds were tested as hosts for commercial emitters: blue phosphor, bis[2-(4,6-difluorophenyl)pyridinato-C2,N](picolinato)iridium(III) (FIrpic), green and blue thermally-activated delayed fluorescence (TADF) emitters 1,2,3,5-tetrakis(9-carbazolyl)-4,6-dicyanobenzene (4CzIPN) and bis[4-(9,9-dimethyl-9,10-dihydroacridin-10-yl)phenyl]sulfone (DMAC-DPS). Blue phosphorescent OLED based on mCP-t-Bu as the host showed up to 22.0% external quantum efficiency. When doping 4CzIPN into mCP-OMe host, a broad emission with peaks at 388, 514, and 572 nm was observed.
C-Terminal Bioconjugation of Peptides through Photoredox Catalyzed Decarboxylative Alkynylation
Garreau, Marion,Le Vaillant, Franck,Waser, Jerome
supporting information, p. 8182 - 8186 (2019/05/21)
We report the first decarboxylative alkynylation of the C-terminus of peptides starting from free carboxylic acids. The reaction is fast, metal-free, and proceeds cleanly to afford alkynylated peptides with a broad tolerance for the C-terminal amino acid. By the use of hypervalent iodine reagents, the introduction of a broad range of functional groups was successful. C-terminal selectivity was achieved by differentiation of the oxidation potentials of the carboxylic acids based on the use of fine-tuned organic dyes.
Sterically Hindered Amination of Aryl Chlorides Catalyzed by a New Carbazolyl-Derived P,N-Ligand-Composed Palladium Complex
Choy, Pui Ying,Kwong, Fuk Yee,Lai, Wing In,Leung, Man Pan
supporting information, p. 2678 - 2686 (2019/06/19)
A family of 2-(9 H -carbazol-9-yl)phenyl-based phosphine ligands were synthesized and their efficacy in promoting the steric hindered Buchwald-Hartwig amination was evaluated. In the presence of Pd(OAc) 2 (0.03-1.0 molpercent) associated with t
"on Water" Promoted Ullmann-Type C-N Bond-Forming Reactions: Application to Carbazole Alkaloids by Selective N-Arylation of Aminophenols
Chakraborti, Gargi,Paladhi, Sushovan,Mandal, Tirtha,Dash, Jyotirmayee
, p. 7347 - 7359 (2018/07/29)
The Ullmann-type cross coupling of a variety of aromatic, aliphatic amines with aryl halides is reported using a CuI-based catalytic system in combination with an easily accessible prolinamide ligand in aqueous media. The method is mild and tolerant to air, moisture, and a wide range of functional groups, providing a novel way to access a variety of aminated products. Secondary amines like heteroaromatic amines and nucleobases have also been used, affording the corresponding coupling products in good to excellent yields. Moreover, this method has been employed for chemoselective C-N arylation of aminophenols and further utilized for the synthesis of carbazole natural products, avoiding the protection and deprotection steps.
