Synthesis of small and large fused bicyclic compounds by tandem dienyne ring-closing metathesis.

A tandem ring-closing metathesis reaction using ruthenium catalyst was carried out to synthesize various fused bicyclic compounds containing both small and large rings. Fast ring-closure of the small ring and slow ring-closure of the large ring resulted in the formation of only one isomer. Further manipulation such as the Diels-Alder reaction was carried out to prepare a complex molecule containing multiple rings of different sizes.