Selective Synthesis of Eight-Membered Cyclic Ureas by the [6 + 2] Cycloaddition Reaction of 2-Vinylazetidines and Electron-Deficient Isocyanates
摘要:
The [6 + 2] cycloaddition reaction of 2-vinylazetidines with electron-deficient isocyanates such as tosyl Isocyanate proceeded smoothly in the absence of the catalyst at room temperature, and various cyclic ureas were isolated in good to high yields. Electron-deficient allenes also reacted with the 2-vinylazetidine, and the corresponding azocine derivatives were isolated.
The cycloadditionreaction of 2-vinylazetidines with benzyne proceeded smoothly without a catalyst, and various benzazocine derivatives were isolated in good to high yields. The scope of the reaction, as well as the reactions of other arynes, has been studied.
The Photochemical Reaction of Vinylaziridines and Vinylazetidines with Chromium(0) and Molybdenum(0) (Fischer) Carbene Complexes
作者:Alexandra R. Rivero、Israel Fernández、Miguel A. Sierra
DOI:10.1002/chem.201302029
日期:2014.1.27
The [5+2] and [6+2] cycloaddition reactions of vinylaziridines and vinylazetidines with ketenes generated photochemically from chromium(0) and molybdenum(0) Fischercarbenecomplexes have been investigated. These processes constitute a straightforward and efficient route to azepanones and azocinones, respectively. The peculiar electronic properties of the metalated ketenes allow for the introduction
The [6 + 2] cycloaddition reaction of 2-vinylazetidines with electron-deficient isocyanates such as tosyl Isocyanate proceeded smoothly in the absence of the catalyst at room temperature, and various cyclic ureas were isolated in good to high yields. Electron-deficient allenes also reacted with the 2-vinylazetidine, and the corresponding azocine derivatives were isolated.