反应详情

Phenol 25 may be treated with NaH in DMF and then alkylated with an allylic bromide to give ether 30. Claisen rearrangement of 30 under thermal conditions gives ortho-allyl phenol 31. Oxidation of the double bond in 31 with OsO4/NMO followed by cleavage with NaIO4 provides the lactol 32. Jones oxidation then provides lactone 33.