Synthesis of pyrrolo[3,4-c]quinolines by 1,5-electrocyclization of non-stabilized azomethine ylides.
In: Tetrahedron letters (Tetrahedron Lett.), Jg. 44 (2003) ; Nr. 11, S. 2343-2346
Zeitschriftenaufsatz / Fach: Chemie
A new route to the pyrrolo[3,4-c]quinoline ring system was developed via the 1,5-dipolar electrocyclization reactions of azomethine ylides derived from easily available 3-formylquinoline derivs. The products thus obtained included 1,2,5,9b-tetrahydro-2-methyl-4H-pyrrolo[3,4-c]quinolin-4-one derivs. and 2-methyl-4-phenyl-2H-pyrrolo[3,4-c]quinoline derivs. The intermediacy of azomethine ylides was shown by the trapping of the proposed dipoles with N-phenylmaleimide.