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1.
Chao Duan Jianwei Zhang Shali Cai Junjun Xiang Prof. Xiaodi Yang Prof. Xike Gao 《European journal of organic chemistry》2023,26(5):e202201347
Linear polycyclic systems are promising candidates in the area of organic electronics. Herein, we present the syntheses of three azulene-indole (AzIn) fused polycyclic heteroaromatics (PHAs), AzIn - 1 , AzIn - 2 and DGAzIn , which have nitrogens and nonhexagonal rings simultaneously. The chemical structures, optical and electrochemical properties of three AzIn-based PHAs have been investigated, as well as their protonation behaviors with trifluoroacetic acid (TFA). All three AzIn-based PHAs exhibit narrow optical band gaps with moderate to good air stability, anti-Kasha emission and reversible stimuli-responsiveness. Furthermore, these straightforward and simple synthetic routes would provide a new entry for constructing novel azulene-embedded π-conjugates, especially for the seven-membered ring of azulene unit, wherein the regioselective transformation is not well developed. 相似文献
2.
5,11-Diazadibenzo[hi,qr]tetracene: Synthesis,Properties, and Reactivity toward Nucleophilic Reagents
Dr. Keisuke Fujimoto Satoshi Takimoto Shota Masuda Dr. Toshiyasu Inuzuka Kazutaka Sanada Prof. Dr. Masami Sakamoto Prof. Dr. Masaki Takahashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(35):8951-8955
5,11-Diazadibenzo[hi,qr]tetracene was synthesized as a new nitrogen-substituted polycyclic heteroaromatic compound by Pd-catalyzed cycloisomerization of an alkyne precursor followed by oxidative cyclization with bis(trifluoroacetoxy)iodobenzene. The substitution of imine-type nitrogen atoms significantly enhanced its electron-accepting character and facilitated the direct nucleophilic addition of arylamines under strongly basic conditions to afford the desired amino-substituted products. The introduction of amino groups induced a remarkable red-shift in their absorption spectra; the tetrasubstituted product exhibited intense near-infrared absorbing property. Furthermore, the π-electronic system, which includes a redox-active 1,4-diazabutadiene moiety, underwent reversible interconversion to its corresponding reduced form upon reduction with NaBH4 and aerobic oxidation. 相似文献
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4.
Skorić I Basarić N Marinić Z Visnjevac A Kojić-Prodić B Sindler-Kulyk M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(2):543-551
New heteroaryl-substituted o-divinylbenzenes, 2,2'-(1,2-phenylenedivinylene)difuran (9), 2,2'-(1,2-phenylenedivinylene)bisbenzo[b]furan (10), and 2,2'-(1,2-phenylenedivinylene)bisnaphtho[2,1-b]furan (11), were prepared and irradiated at various concentrations; intramolecular photocycloaddition and intermolecular [2+2] twofold photoaddition reactions took place to give bicyclo[3.2.1]octadiene derivatives 12-14 and cyclophane derivatives 15-17, respectively. Compound 11 was the most selective of these o-divinylbenzenes, which, owing to pi-pi intra- or intermolecular complexation, gave only the exo-bicyclo[3.2.1]octadiene derivative 14 at low concentrations, and only the cyclophane derivative 17 at high concentrations. 相似文献
5.
Masilamani Jeganmohan Dr. Sivakolundu Bhuvaneswari Dr. Chien‐Hong Cheng Prof. Dr. 《化学:亚洲杂志》2010,5(1):153-159
The reaction of benzynes with N‐heteroaromatics including quinolines, isoquinolines, and pyridines and various terminal alkynes or ketones with an α‐hydrogen in the presence of KF and 18‐crown‐6 in THF at room temperature for 8 h gave various N‐arylated 1,2‐dihydroheteroaromatics in good to moderate yields. Some of these product structures are found in various naturally occurring and biologically active heterocyclic compounds. The reaction involves an unusual multiple construction of new C? C, C? N, and C? H bonds and the cleavage of a C? H bond in one pot. It is likely that the three‐component coupling proceeds through the nucleophilic addition of quinoline to benzyne, which generates a zwitterionic species. The latter then attracts a proton from terminal alkyne (or ketone) to generate an N‐arylated quinolinium cation and an acetylide anion. Further reaction of these two ions provides the final substituted 1,2‐dihydroquinolines. In the reaction, the terminal alkyne acts first as a proton donor and then as a nucleophile. The application of a three‐component coupling reaction product, 1,2‐dihydro‐2‐pyridinyl alkyne in a stereospecific [4+2] Diels–Alder cycloaddition reaction with N‐phenyl maleimide to give an isoquinuclidine derivative, an important core present in various natural products, is demonstrated. 相似文献
6.
Feifei Han Jinhua Li Dr. Hong Zhang Dr. Tongdao Wang Prof. Dr. Zhenyang Lin Prof. Dr. Haiping Xia 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(2):565-567
The transformations of metallabenzene to substituted benzenes have been achieved by reactions of osmabenzenes with silver/copper acetylides. In this investigation, novel tetraphenylphosphonium salts containing two phosphonium substituents on the same benzene ring are generated. 相似文献
7.
Clve D. Mboyi Delphine Vivier Ahmad Daher Paul Fleurat‐Lessard Hlne Cattey Charles H. Devillers Claire Bernhard Franck Denat Julien Roger Jean‐Cyrille Hierso 《Angewandte Chemie (International ed. in English)》2020,59(3):1149-1154
Click chemistry at a tetrazine core is useful for bioorthogonal labeling and crosslinking. Introduced here are two new classes of doubly clickable s‐aryl tetrazines synthesized by Cu‐catalyzed cross‐coupling. Homocoupling of o‐brominated s‐aryl tetrazines leads to bis(tetrazine)s structurally characterized by tetrazine cores arranged face‐to‐face. [N]8 π‐stacking interactions are essential to the conformation. Upon inverse electron demand Diels–Alder (iEDDA) cycloaddition, the bis(tetrazine)s produce a unique staple structure. The o‐azidation of s‐aryl tetrazines introduces a second proximal intermolecular clickable function that leads to double click chemistry opportunities. The stepwise introduction of fluorophores and then iEDDA cycloaddition, including bioconjugation to antibodies, was achieved on this class of tetrazines. This method extends to (thio)etherification, phosphination, trifluoromethylation and the introduction of various bioactive nitrogen‐based heterocycles. 相似文献
8.
Pyrroles and indoles react smoothly with α-diazocarbonyl compounds in the presence of 10 mol% of InBr3 under mild conditions to afford the corresponding 2- and 3-alkyl pyrrole and 3-alkyl indole derivatives, respectively, in good yields with high selectivity. 相似文献
9.
Dr. Takuya Nakashima Kazuhiko Imamura Kyohei Yamamoto Yuka Kimura Shohei Katao Yuichiro Hashimoto Prof. Tsuyoshi Kawai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(42):13722-13729
α,β‐Linked oligothiazoles with head‐to‐tail connectivity are presented as a new family of helical scaffolds. Combinations of palladium‐catalyzed cross‐coupling reactions at the 5‐ and 4‐positions of 2‐phenylthiazole led to the synthesis of oligo(2‐phenylthiazoles) with ortho linkages with a variety of defined sequences. The secondary structures of the α,β‐linked oligo(2‐phenylthiazoles) showed a clear dependence on their sequences. X‐ray crystallography of the trimer, tetramer, and hexamer with head‐to‐tail connection revealed the formation of a helical structure, which was stabilized by a combination of intramolecular forces, including interheteroatom (S???N), CH–π, and π–π interactions. The introduction of a chiral end‐group successfully led to the induction of chirality into the helical conformations. Programmable sequences for controlled geometries and photofunctions have been demonstrated through the manifold connection pathways in α,β‐linked oligothiazoles. 相似文献
10.
An efficient method for the synthesis of 5-SF5 substituted indazoles from commercially available 4-nitro-(pentafluorosulfanyl)benzene through vicarious nucleophilic substitution of hydrogen (VNS) reaction, reduction of nitro group and cyclization of resulting anilines were described. Transformations of 5-SF5-indazoles led to a variety of SF5-substiuted heteroarenes that can serve as a versatile building block for diversity-oriented organic synthesis. 相似文献