Preparation of some isoindolo[2,1-f]phenanthridine derivatives

Abstract

3-o-Biphenylylaminophthalide derivatives on treatment with hot phosphoric trichloride or polyphosphoric acid are converted by rearrangement and cyclodehydration into isoindolo[2,1-f]phenanthridin-10(14bH)-ones. Some other synthetic approaches to this new ring system are explored. The ψ-chloride obtained from 2-(6-phenanthridyl) benzoic acid (26) is also an isoindolo[2,1-f]phenanthridine derivative; some of its reactions give ring-opened products related to the acid (26).