Modular synthesis of 3-substituted isocoumarins <i>via</i> silver-catalyzed aerobic oxidation/<i>6-endo</i> heterocyclization of <i>ortho</i>-alkynylbenzaldehydes
作者:Hao Wu、Yi-Chun Wang、Andrey Shatskiy、Qiu-Yan Li、Jian-Quan Liu、Markus D. Kärkäs、Xiang-Shan Wang
DOI:10.1039/d1ob01065d
日期:——
A method involving silver-catalyzed aerobic oxidation/6-endo heterocyclization of ortho-alkynylbenzaldehydes to yield 3-substituted isocoumarins is described. The developed protocol allows convenient access to a range of synthetically useful 3-substituted isocoumarins and related fused heterocyclolactones in good to high yields, using silver tetrafluoroborate as the catalyst, and atmospheric oxygen
NHC-Catalyzed Oxidative Cyclization Reactions of 2-Alkynylbenzaldehydes under Aerobic Conditions: Synthesis of O-Heterocycles
作者:Jong Hyub Park、Sachin V. Bhilare、So Won Youn
DOI:10.1021/ol200481u
日期:2011.5.6
An NHC-catalyzed, regio- and stereoselective oxidative cyclization of o-alkynylbenzaldehydes bearing an unactivated alkyne moiety as an internalelectrophile has been developed to afford phthalides and isocoumarins. A single organocatalytic system enabled two sequential C−O bond formations to take place in an atom economical manner via highly efficient dual activation. Molecular oxygen in air could