A general route to 5,6-seco-hexahydrodibenzopyrans and analogues: first total synthesis of (+)-Machaeridiol B and (+)-Machaeriol B

A general and efficient route for the synthesis of 5,6-seco-hexahydrodibenzopyran and trans-hexahydrodibenzopyran analogues was established, via a highly regio- and stereoselective SN2′ reaction of arylcyanocuprates to enol silyl ether of α,β-epoxycyclohexanone. It was applied to the first facile total synthesis of (+)-Machaeridiol B and (+)-Machaeriol B.