Asymmetric Total Synthesis of Cryptorigidifoliol I.

An efficient asymmetric total synthesis of cryptorigidifoliol I based on an unusual Luche reduction leading to bicyclic etherification and acid hydrolysis to a thermodynamically less stable 4-hydroxy-2,6- trans -disubstituted-THP moiety has been achieved. The easy setup of trans -2,6-substitution on the core pyran ring through bicyclic etherification would enable the synthesis of various THP and bicyclic-THP-lactone natural products.