First approach to the frondosin C ring system via a tandem cyclization/Claisen rearrangement sequence

[GRAPHICS] A one-pot tandem 5-exo cyclization/Claisen rearrangement strategy is utilized as the key step in the straightforward construction of the tetracyclic ring system of frondosin C. This reaction is done under microwave irradiation in the presence of catalytic MeLi.