171258-08-5Relevant academic research and scientific papers
Superparamagnetic nanoparticles-supported phosphine-free palladium catalyst for the Sonogashira coupling reaction
Phan, Nam T.S.,Le, Ha V.
, p. 130 - 138 (2011)
Superparamagnetic nanoparticles were synthesized following a microemulsion method, and functionalized with Schiff-base groups on the surface to form immobilized bidentate ligands. The functionalized nanoparticles were complexed with palladium acetate, aff
Concise synthesis of 1,2-dihydroisoquinolines and 1H-isochromenes by carbophilic lewis acid-catalyzed tandem nucleophilic addition and cyclization of 2-(1-alkynyl)arylaldimines and 2-(1-alkynyl)arylaldehydes
Obika, Shingo,Kono, Hideki,Yasui, Yoshizumi,Yanada, Reiko,Takemoto, Yoshiji
, p. 4462 - 4468 (2007)
(Chemical Equation Presented) By using carbophilic Lewis acids, In(OTf)3, NiCl2, and AuCl(PPh3)/AgNTf 2, a concise and efficient synthesis of 1,3-disubstituted 1,2-dihydroisoquinolines has been achieved via tandem nucleophilic addition and cyclization of 2-(1-alkynyl)arylaldimines. Addition of proton sources such as water, CF3CH2OH, and 2,6-di-tert-butyl-4-methoxyphenol was essential for the Lewis acid-catalyzed tandem reactions with organometallic reagents. By switching these catalysts, various types of nucleophiles such as allylstannanes, silyl enol ethers, alkenylboronic acids, and active methylene compounds could be introduced at the C1 position of 1,2-dihydroisoquinolines in this transformation. Furthermore, this method proved to be applicable to the synthesis of 1H-isochromene derivatives via the same tandem reaction of 2-(1-alkynyl)-arylaldehydes.
Silver/Rhodium Relay Catalysis Enables C?H Functionalization of In Situ Generated Isoquinolines with Sulfoxonium Ylides: Construction of Hexahydrodibenzo[a,g]quinolizine Scaffolds
Li, Quanzhe,Liu, Ruixing,Wei, Yin,Shi, Min
supporting information, p. 2664 - 2669 (2021/04/05)
Employing silver/rhodium relay catalysis strategy, an intramolecular electrophilic cyclization and C?H activation followed by cascade hydrogenation and reductive amination has been developed. The acylmethylated isoquinoline derivatives could be afforded with broad substrate scope in 23–88% yields, which could be further transformed to the core skeleton of hexahydrodibenzo[a,g]quinolizine as drug-candidates. Moreover, this reaction was achieved in a gram-scale. A reasonable reaction mechanism has been proposed based on a series of control and KIE experiments. (Figure presented.).
Single Cu(I)-Photosensitizer Enabling Combination of Energy-Transfer and Photoredox Catalysis for the Synthesis of Benzo[ b]fluorenols from 1,6-Enynes
Zheng, Limeng,Xue, Han,Zhou, Bingwei,Luo, Shu-Ping,Jin, Hongwei,Liu, Yunkui
, p. 4478 - 4482 (2021/05/26)
An efficient, mild, and atom-economical synthesis of benzo[b]fluorenols from 1,6-enynes has been developed under photocatalytic conditions. A single P/N heteroleptic Cu(I)-photosensitizer might exhibit both energy-transfer and photoredox catalytic activities in the formation of benzo[b]fluorenols.
Mechanistic Investigation of the Formation of Isoindole N-Oxides in the Electron Transfer-Mediated Oxidative Cyclization of 2′-Alkynylacetophenone Oximes
Kim, Wan Shin,Espinoza Castro, Victor M.,Abiad, Amanda,Ko, Michael,Council, Ashley,Nguyen, Anh,Marsalla, Laura,Lee, Vicky,Tran, Thao,Petit, Andrew S.,De Lijser, H. J. Peter
, p. 693 - 708 (2021/01/09)
This paper describes a joint experiment-theory investigation of the formation and cyclization of 2′-alkynylacetophenone oxime radical cations using photoinduced electron transfer (PET) with DCA as the photosensitizer. Using a combination of experimental 1H and 13C nuclear magnetic resonance (NMR) spectra, high-resolution mass spectrometry, and calculated NMR chemical shifts, we identified the products to be isoindole N-oxides. The reaction was found to be stereoselective; only one of the two possible stereoisomers is formed under these conditions. A detailed computational investigation of the cyclization reaction mechanism suggests facile C-N bond formation in the radical cation leading to a 5-exo intermediate. Back-electron transfer from the DCA radical anion followed by barrierless intramolecular proton transfer leads to the final product. We argue that the final proton transfer step in the mechanism is responsible for the stereoselectivity observed in experiment. As a whole, this work provides new insights into the formation of complex heterocycles through oxime and oxime ether radical cation intermediates produced via PET. Moreover, it represents the first reported formation of isoindole N-oxides.
Visible-Light-Induced Cyclization/Aromatization of 2-Vinyloxy Arylalkynes: Synthesis of Thio-Substituted Dibenzofuran Derivatives
Chen, Hui,Chen, Yanyan,Mo, Zuyu,Xu, Yanli,Yan, Yunyun,Zhang, Niuniu
, p. 376 - 381 (2021/01/13)
A visible-light-induced cascade reaction of 2-vinyloxy arylalkynes with thiosulfonates was developed and provided unexpected thio-substituted dibenzofuran derivatives in moderate yields. Mechanistic studies revealed the thiosulfonylation product of 2-vinyloxy arylalkyne was the key intermediate, and the additive disulfide played the role of hydrogen abstraction in the aromatization process to offer the desired product. This reaction presents a new reaction mode for the construction of polycyclic oxygen heterocycles.
Regio- and stereoselective intramolecular hydroalkoxylation of aromatic alkynols: an access to dihydroisobenzofurans under transition-metal-free conditions
Yu, Shu-Yan,Gao, Li-Hong,Wu, Jing-Xin,Lan, Hong-Bing,Ma, Yi,Yin, Zhi-Gang
, p. 3303 - 3310 (2020/04/27)
An efficient, transition-metal-free method to synthesize dihydroisobenzofuran derivatives via intramolecular hydroalkoxylation of aromatic alkynols with the promotion of cesium carbonate has been developed. The reaction proceeds regioselectively with exclusive formation of 5-exo-dig product, and only Z-isomer of the new generated double bond is observed. This new protocol features with milder reaction conditions, more convenient operation and satisfactory selectivities.
Palladium-catalyzed cascade decarboxylative amination/6- endo-dig benzannulation of o-alkynylarylketones with n-hydroxyamides to access diverse 1-naphthylamine derivatives
Zuo, Youpeng,He, Xinwei,Tang, Qiang,Hu, Wangcheng,Zhou, Tongtong,Shang, Yongjia
supporting information, p. 3890 - 3894 (2020/05/18)
An efficient and practical one-pot strategy to produce highly substituted 1-naphthylamines via sequential palladium-catalyzed decarboxylative amination/intramolecular 6-endo-dig benzannulation reactions has been described. In this reaction, a broad range of electron-rich, electron-neutral, and electron-deficient o-alkynylarylketones react well with N-hydroxyl aryl/alkylamides to give a diversity of 1-naphthylamines in good to excellent yields under mild reaction conditions. The gram-scale synthesis, with benefits such as undiminished product yield and easy transformation, illustrated the practicality of this method.
Palladium-Catalyzed Dialkylation of C-C Triple Bonds: Access to Multi-Functionalized Indenes
Liu, Xiao-Wei,Li, Shu-Sen,Dai, Dong-Ting,Zhao, Meng,Shan, Cui-Cui,Xu, Yun-He,Loh, Teck-Peng
supporting information, p. 3696 - 3700 (2019/05/24)
A palladium-catalyzed dialkylation of 1,3-dien-5-ynes was developed using alkenyl double bonds as the initiator and terminator for the synthesis of functionalized indene derivatives. The reactions were performed under mild reaction conditions, affording the corresponding multi-substituted indene derivatives in high efficiency via unprecedented 5-endo cyclization and alkylation processes. It was found that the substituent location at the alkenyl double bond was essential for the chemoselective synthesis of the indene and naphthalene derivatives, respectively.
CuI/Cu(OTf)2/DMSO system-catalyzed intramolecular oxidative cyclization of (o-alkynyl)arylketones: Efficient synthesis of 1,4-naphthoquinones
Zhou, Bingwei,Liu, Qian,Wang, Heng,Jin, Hongwei,Liu, Yunkui
, p. 3815 - 3821 (2019/06/14)
A concise and efficient method for the synthesis of 1,4-naphthoquinones has been successfully developed involving a CuI/Cu(OTf)2/DMSO system-catalyzed intramolecular oxidative cyclization of (o-alkynyl)arylketones. The present protocol provided a novel approach to access functionalized 1,4-naphthoquinones from non-naphthoquinone precursors with good selectivity and functional group tolerance.
