Synthesis of enantiomerically pure oxygen-containing helical heterocycles via stereospecific rearrangement of benzofused-2,2′-diphenoquinone derivatives

Three different enantiomerically pure poly-condensed oxygen-containing heterocyclic compounds were synthesized by the rearrangement of enantiomerically pure (P)- and (M)-benzofused-2,2′-diphenoquinones. The three products were: a spiro compound bearing a γ-lactone ring, and two derivatives with a helical structure, one containing a δ-lactone ring and the other oxepin and furan rings. When the helical quinone derivative was heated in solution, the rearrangement proceeded with retention of configuration. Thus, (P)-quinone derivatives gave the corresponding (S)-spiro and (P)-helicene-like derivatives without compromising their enantiomeric purity, and vice versa.