The first example of phenanthroline- BuOK promoted intramolecular radical C-H arylation of N-(2-iodobenzyl)indoles without involvement of transition metals has been developed. A variety of substituted 6 H-isoindolo [2, 1-a] indoles were prepared by a simple and efficient intramolecular cyclization using 1,10-phenanthroline in the presence of potassium tert-butoxide and chlorobenzene. This strategy provides a fast and versatile access to isoindolo[2,1- a]indole derivatives for the synthesis of pharmaceuticals and organic electroluminescent (EL) materials.