15638-06-9Relevant academic research and scientific papers
Converting homogeneous to heterogeneous in electrophilic catalysis using monodisperse metal nanoparticles
Witham, Cole A.,Huang, Wenyu,Tsung, Chia-Kuang,Kuhn, John N.,Somorjai, Gabor A.,Toste, F. Dean
, p. 36 - 41 (2010)
A continuing goal in catalysis is to unite the advantages of homogeneous and heterogeneous catalytic processes. To this end, nanoparticles represent a new frontier in heterogeneous catalysis, where this unification can also be supplemented by the ability
Modular Synthesis of Organoboron Helically Chiral Compounds: Cutouts from Extended Helices
Full, Julian,Panchal, Santosh P.,G?tz, Julian,Krause, Ana-Maria,Nowak-Król, Agnieszka
, p. 4350 - 4357 (2021/01/29)
Two types of helically chiral compounds bearing one and two boron atoms were synthesized by a modular approach. Formation of the helical scaffolds was executed by the introduction of boron to flexible biaryl and triaryl derived from small achiral building blocks. All-ortho-fused azabora[7]helicenes feature exceptional configurational stability, blue or green fluorescence with quantum yields (Φfl) of 18–24 % in solution, green or yellow solid-state emission (Φfl up to 23 %), and strong chiroptical response with large dissymmetry factors of up to 1.12×10?2. Azabora[9]helicenes consisting of angularly and linearly fused rings are blue emitters exhibiting Φfl of up to 47 % in CH2Cl2 and 25 % in the solid state. As revealed by the DFT calculations, their P–M interconversion pathway is more complex than that of H1. Single-crystal X-ray analysis shows clear differences in the packing arrangement of methyl and phenyl derivatives. These molecules are proposed as primary structures of extended helices.
Method for synthesizing phenanthrene and derivatives thereof
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Paragraph 0072-0083, (2019/03/26)
The present invention provides a method for synthesizing phenanthrene and derivatives thereof represented by a formula (III) or (IV). The method is characterized in that a substituted 2-phenylcinnamaldehyde compound represented by a formula (I) or 2-thiophenylcinnamaldehyde represented by a formula (II) is taken as an initial substance, under the effect of a silver catalyst, an oxidant, a basic substance and a solvent, a reaction is carried out at 60 DEG C-100 DEG C for 12-36 hours, the reaction solution is separated and purification is carried out, so that corresponding phenanthrene and derivatives thereof represented by the formula (III) or (IV) are obtained. The synthesis method of the invention has the characteristics of small environmental hazard, mild reaction conditions, simple operation and the like.
A combined experimental and computational study on the cycloisomerization of 2-ethynylbiaryls catalyzed by dicationic arene ruthenium complexes
Yamamoto, Yoshihiko,Matsui, Kazuma,Shibuya, Masatoshi
supporting information, p. 7245 - 7255 (2015/05/05)
Ruthenium-catalyzed cycloisomerization of 2-ethynylbiaryls was investigated to identify an optimal ruthenium catalyst system. A combination of [η6-(p-cymene)RuCl2(PR3)] and two equivalents of AgPF6 effectively converted 2-ethynylbiphenyls into phenanthrenes in chlorobenzene at 120 °C over 20 h. Moreover, 2-ethynylheterobiaryls were found to be favorable substrates for this ruthenium catalysis, thus achieving the cycloisomerization of previously unused heterocyclic substrates. Moreover, several control experiments and DFT calculations of model complexes were performed to propose a plausible reaction mechanism.
Base-Promoted/Gold-Catalyzed Intramolecular Highly Selective and Controllable Detosylative Cyclization
Zhu, Chenghao,Qiu, Lin,Xu, Guangyang,Li, Jian,Sun, Jiangtao
supporting information, p. 12871 - 12875 (2015/09/07)
A highly selective, controllable and synthetically useful base-promoted intramolecular detosylative cyclization of bis-N-tosylhydrazones has been achieved, affording N-containing heterocycles and cyclic olefins under transition-metal-free or gold-catalyzed procedures, respectively. Moreover, an effective and practical metal-free or gold-catalyzed approach to synthesize polycyclic aromatic compounds is also reported. Basic cyclizations: A highly selective, controllable, and synthetically useful base-promoted intramolecular detosylative cyclization of bis-N-tosylhydrazones affords N-containing heterocycles and cyclic olefins under transition-metal-free or gold-catalyzed procedures, respectively. Moreover, an effective and practical metal-free or gold-catalyzed approach to synthesize polycyclic aromatic compounds is also reported.
Au(i)-catalyzed triple bond alkoxylation/dienolether aromaticity-driven cascade cyclization to naphthalenes
Liu, Yongxiang,Guo, Jia,Liu, Yang,Wang, Xiaoyu,Wang, Yanshi,Jia, Xinyu,Wei, Gaofei,Chen, Lizhu,Xiao, Jianyong,Cheng, Maosheng
supporting information, p. 6243 - 6245 (2014/06/09)
A novel strategy for the synthesis of multisubstituted naphthalenes was developed via a Au(i)-catalyzed alkyne alkoxylation/dienolether aromaticity-driven cascade cyclization using 1,5-enyne substrates. The functional group toleration was examined by synthesizing a series of substrates and the mechanism was also studied based on intermediates isolated through deuterium labeling experiments. This journal is the Partner Organisations 2014.
A scalable and expedient route to 1-Aza[6]helicene derivatives and its subsequent application to a chiral-relay asymmetric strategy
Weimar, Marko,Correa Da Costa, Rosenildo,Lee, Fu-Howe,Fuchter, Matthew J.
supporting information, p. 1706 - 1709 (2013/06/27)
A rapid route to diversely functionalized 1-aza[6]helicenes has been achieved via the development of a copper-mediated cross-coupling reaction, followed by PtCl4-catalyzed cycloisomerization. Not only does this method allow access to these func
Rhodium(II)-catalyzed cyclization of bis(N-tosylhydrazone)s: An efficient approach towards polycyclic aromatic compounds
Xia, Ying,Liu, Zhenxing,Xiao, Qing,Qu, Peiyuan,Ge, Rui,Zhang, Yan,Wang, Jianbo
supporting information; experimental part, p. 5714 - 5717 (2012/07/28)
Ahead of the PAC: Polycyclic aromatic compounds (PACs) can be easily accessed by the combination of Suzuki-Miyaura cross-coupling and a [Rh 2(OAc)4]-catalyzed carbene reaction using easily available bis(N-tosylhydrazone)s as intermediates (see scheme; Ts=4-toluenesulfonyl). Copyright
Studies towards the total synthesis of Sch 56036; isoquinolinone synthesis and the synthesis of phenanthrenes
Walker, Edward R.,Leung, Shing Y.,Barrett, Anthony G.M.
, p. 6537 - 6540 (2007/10/03)
The isoquinolinone hemisphere of Sch 56036 has been prepared using a modified Pomeranz-Fritsch reaction and the synthesis of the phenanthrene core has been modelled via a Suzuki coupling and subsequent ring closing metathesis.
Synthesis of phenanthrenes and polycyclic heteroarenes by transition-metal catalyzed cycloisomerization reactions
Mamane, Victor,Hannen, Peter,Fuerstner, Alois
, p. 4556 - 4575 (2007/10/03)
Readily available biphenyl derivatives containing an alkyne unit at one of their ortho-positions are converted into substituted phenanthrenes on exposure to catalytic amounts of either PtCl2, AuCl, AuCl3, GaCl3 or InCl3 in toluene. This 6-endo-dig cyclization likely proceeds through initial π-complexation of the alkyne unit followed by interception of the resulting η2-metal species by the adjacent arene ring. The reaction is inherently modular, allowing for substantial structural variations and for the incorporation of substituents at any site of the phenanthrene product. Moreover, it is readily extended to the heterocyclic series as exemplified by the preparation of benzoindoles, benzocarbazoles, naphthothiophenes, as well as bridgehead nitrogen heterocycles such as pyrrolo[1,2-a]quinolines. Depending on the chosen catalyst, biaryls bearing halo-alkyne units can either be converted into the corresponding 10-halo-phenanthrenes or into the isomeric 9-halo-phenanthrenes; in the latter case, the concomitant 1,2-halide shift is best explained by assuming a metal vinylidene species as the reactive intermediate. The scope of this novel method for the preparation of polycyclic arenes is illustrated by the total synthesis of a series of polyoxygenated phenanthrenes that are close relatives of the anticancer agent combretastatin A-4, as well as by the total synthesis of the aporphine alkaloid O-methyl-dehydroisopiline and its naturally occurring symmetrical dimer.
