1374563-01-5Relevant academic research and scientific papers
Cycloaddition of C,C-disubstituted ketonitrones with acceptor methylenecyclopropanes and subsequent rearrangement cascade of 5-spirocyclopropane-isoxazolidines
Tran, Tung Q.,Diev, Vyacheslav V.,Starova, Galina L.,Gurzhiy, Vladislav V.,Molchanov, Alexander P.
, p. 2054 - 2061 (2012)
A new reaction cascade to give tricyclic cores of 2,4-dihydro-1H-azeto[1,2- a]quinolines (benzocarbacephems) and pyrrolo[1,2-a]quinolines starting from acyclic N-aryl ketonitrones and acceptor ring substituted methylenecyclopropanes has been reported. This reaction includes 1,3-dipolar cycloaddition of N-aryl-C,C-diaryl or N-aryl-C,C-bis(methoxycarbonyl) nitrones 1 to the double bond of dimethyl methylenecyclopropane-1,2-dicarboxylate 2 or benzylidenecyclopropane-1,1-dicarboxylate 3, followed by Brandi-Guarna rearrangement of the initially formed 5-spirocyclopropane-isoxazolidine cycloadducts to give 2,4-dihydro-1H-azeto[1,2-a]quinolines 4 or pyrrolo[1,2-a]quinolines 6. 1,3-Dipolar cycloaddition of acceptor ring-substituted methylenecyclopropanes and trisubstituted N,C,C-triaryl- and N-aryl-C,C-bis(methoxycarbonyl)nitrones proceed with the formation of new polycycliccompounds with azeto[1,2-a]quinoline or pyrrolo[1,2-a]quinoline cores. Copyright
