Dibenzo[2,3:5,6]pyrrolizino[1,7-bc]indolo[1,2,3-lm]carbazole: a new electron donor

The new heterocyclic system, dibenzo[2,3:5,6]pyrrolizino[1,7-bc]indolo[1,2,3-lm]carbazole 3, which can be considered as a planar hybrid of carbazole and p-phenylenediamine, can readily be prepared from commercial precursors and possesses high thermal stability and strong electron donor properties comparable to tetra- and pentacene.