Title of article :
Synthesis and dynamic NMR study of indole derivatives
Author/Authors :
Shams-Najafi, Jalal Department of Chemistry - Faculty of Sciences - Ferdowsi University of Mashhad, Mashhad, Iran , Rostami-Charati, Faramarz Research Center for Conservation of Culture Relicst (RCCCR) - Research institute of Cultural Heritage &Tourism, Tehran, Iran
Abstract :
Protonation of the highly reactive 1:1 intermediates produced in the reaction between alkyl(aryl) isocyanides and dibenzoylacetylene by isatin, leads to vinylnitrilium cations, which undergo carbon-centered Michael type addition with the conjugate base of the NH-acid to produce highly functionalized indole-2,3-diones. A dynamic NMR effect is observed in the 1H NMR spectra of these compounds as a result of restricted rotation around the single bond linking the indole moiety and the furan system. The free-energy of activation (ΔG#) for this process is 69-71 kJ mol-1.
Keywords :
Dibenzoylacetylene , Isatin , Alkyl (aryl) isocyanides , Dynamic NMR
Journal title :
Iranian Journal of Organic Chemistry
