Tandem cyclization–cycloaddition reactions of α-diazo ketones with macrocyclic olefins in the presence of rhodium (II) acetate catalyst led to the oxanorbornane fused macrocyclic di- or tetralactone ring systems in moderate yield. This forms the first example of 1, 3-dipolar cycloaddition reactions with a macrocyclic olefin as a dipolarophile, affording a variety of new oxanorbornane fused macrocycles with diastereoselectivity.
