Lewis acid-catalyzed [3+3] annulation of donor-acceptor cyclopropanes and indonyl alcohols: one step synthesis of substituted carbazoles with promising photophysical properties

Abstract

A highly efficient protocol to access carbazole from donor−acceptor cyclopropane and indonyl alcohol via [3+3] annulation in the presence of a Lewis acid has been demonstrated. This method facilitates the post functionalization of the substituted carbazole into a fully conjugated π-system exhibiting intense emission bands in the visible range of the spectrum and also offers a convenient route toward the synthesis of pityriazole derivatives.