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341.
R. R. Gataullin I. S. Afon'kin A. A. Fatykhov L. V. Spirikhin I. B. Abdrakhmanov 《Russian Chemical Bulletin》2000,49(1):122-124
The reaction ofN-acetyl-2-(cyclohex-1-enyl)aniline with Br2 orN-bromsuccinimide at 20°C is accompanied by intramolecular cyclization to give brominated 3,1-benzoxazines or 4-acetyl-(3-bromo-5-methyl-1,2,3,3a,4,8b-hexahydrocyclopenta[b]indole.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 118–120, January, 2000. 相似文献
342.
343.
Shoji Yoshimoto Fumihiko Ohashi Tetsuya Kameyama 《Macromolecular rapid communications》2004,25(19):1687-1691
Summary: Conducting polyaniline (PANI) and montmorillonite (MMT) nanocomposites were prepared from aniline sulfate and MMT by a mechanochemical synthesis route. X‐Ray diffraction analysis confirmed that, by controlling the aniline sulfate content, mechanochemical synthesis led to two types of different formations. After polymerization, the mechanochemical route synthesized much more PANI between the clay layers compared to a solution method. The electrical conductivities of the synthesized PANI‐MMT nanocomposites in pressed pellets ranged in the order of between 10−4 and 10−3 S · cm−1.
344.
Ke-Zuan Deng Wen-Liang Jia Prof. Dr. M. Ángeles Fernández-Ibáñez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(9):e202104107
Herein, we report a nondirected para-selective C−H alkynylation of aniline derivatives by a Pd/S,O-ligand-based catalyst. The reaction proceeds under mild conditions and is compatible with a variety of substituted anilines. The scalability and further derivatizations of the alkynylated products have been also demonstrated. 相似文献
345.
Savitha GurunathanParamasivam Thirumalai Perumal 《Tetrahedron letters》2011,52(15):1783-1787
Facile synthesis of novel 3-bromo-1,2-dihydroquinolines by the intramolecular cyclization of N-tosyl-N-propargyl anilines catalyzed by Pd(OAc)2 in conjunction with CuBr2 and LiBr. 相似文献
346.
Benjamin M. Mills Dr. Natalie Fey Dr. Tomasz Marszalek Prof. Wojciech Pisula Patrice Rannou Prof. Charl F. J. Faul 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(47):16950-16956
We have prepared a simple star‐shaped oligo(aniline) ( TDPB ) and characterised it in detail by MALDI‐TOF MS, UV/Vis/NIR spectroscopy, time‐dependent DFT, cyclic voltammetry and EPR spectroscopy. TDPB is part of an underdeveloped class of π‐conjugated molecules with great potential for organic electronics, display and sensor applications. It is redox active and reacts with acids to form radical cations. Acid‐doped TDPB shows behaviour similar to discotic liquid crystals, with X‐ray scattering investigations revealing columnar self‐assembled arrays. The combination of unpaired electrons and supramolecular stacking suggests that star‐shaped oligo(aniline)s like TDPB have the potential to form conducting nanowires and organic magnetic materials. 相似文献
347.
Xiang Zhang 《International journal of quantum chemistry》2015,115(23):1658-1667
The radical arylation of the para‐substituted anilines under three different conditions (A: arylhydrazines as the radical precursors and MnO2 as the oxidant in acetonitrile; B: arylhydrazine hydrochlorides as the radical precursors and O2 as the oxidant in aqueous sodium hydroxide solution; C: arenediazonium salts as the radical precursors and TiCl3 as the reductant in aqueous hydrochloric acid solution) has been theoretically studied and the origins of the ortho/meta regioselectivity have been explored. The arylation process is suggested to contain three steps: radical generation, radical addition, and rearomatization. Calculations show that the arylation of the neutral anilines is kinetically controlled under conditions A and B, and the regioselectivity is determined by the radical addition. As a directing group, ? NH2 plays an important role in these cases with the assistance of Mn(OH)2 (the reduced product of MnO2 under condition A) and Na+ (condition B). As for the arylation of the protonated anilines under condition C, the regioselectivity is affected by the substituents in the para‐position of anilines. Electron‐donating groups support meta‐addition and the selectivity is decided by the radical addition. Conversely, electron‐withdrawing groups favor ortho‐addition, and in this situation the arylation process is thermodynamically controlled and the regioselectivity is determined by the radical addition and rearomatization. © 2015 Wiley Periodicals, Inc. 相似文献
348.
A palladium-catalyzed annulation of 2-(aryldiazenyl) aniline and dimethyl sulfoxide was developed to access N-aryl-1H-benzo[d]imidazol-1-amine in moderate to good yields. Activated by 1,4-diazabicyclo[2.2.2]octane bis(sulfur dioxide) adduct (DABSO), DMSO served as a “CH” fragment during this procedure. It represents a facile pathway leading to benzimidazoles. 相似文献
349.
《Macromolecular bioscience》2017,17(9)
Silk fibroin (SF) with good biocompatibility and degradability has great potential for tissue engineering. However, the SF based scaffolds lack the electroactivity to regulate the myogenic differentiation for the regeneration of muscle tissue, which is sensitive to electrical signal. Herein, a series of electroactive biodegradable scaffolds based on SF and water‐soluble conductive poly(aniline‐co‐N‐(4‐sulfophenyl) aniline) (PASA) via a green method for skeletal muscle tissue engineering are designed. SF/PASA scaffolds are prepared by vortex of aqueous solution of SF and PASA under physiological condition. Murine‐derived L929 fibroblast and C2C12 myoblast cells are used to evaluate cytotoxicity of SF/PASA scaffolds. Moreover, myogenic differentiation of C2C12 cells is investigated by analyzing the morphology of myotubes and related gene expression. These results suggest that electroactive SF/PASA scaffolds with a suitable microenvironment, which can enhance the myogenic differentiation of C2C12 cells, have a great potential for skeletal muscle regeneration. 相似文献
350.
Silver(I)‐Catalyzed N‐Trifluoroethylation of Anilines and O‐Trifluoroethylation of Amides with 2,2,2‐Trifluorodiazoethane 下载免费PDF全文
Dr. Haiqing Luo Guojiao Wu Yan Zhang Prof. Dr. Jianbo Wang 《Angewandte Chemie (International ed. in English)》2015,54(48):14503-14507
A straightforward N‐trifluoroethylation of anilines has been developed based on silver‐catalyzed N? H insertions with 2,2,2‐trifluorodiazoethane (CF3CHN2). Mechanistically, the reaction is proposed to involve migratory insertion of a silver carbene as the key step. In contrast, when amides are employed as the substrates under similar reaction conditions, O‐trifluoroethylation occurs to afford trifluoroethyl imidates. 相似文献