171258-08-5Relevant articles and documents
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
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.).
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.
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.
