Synthesis of 9- and 10-membered macrolactones by selective ozonolysis of 1,4-diazaphenanthrene derivatives

9- and 10-membered macrolactones bearing benzo and diazine rings were obtained by chemoselective ozonolysis of dihydrofuran and pyran 1,4-diazaphenathrene derivatives. This is the first example of preparation of macrolactones by chemoselective ozonolysis of an enol double bond shared by aromatic and heterocyclic rings.