T. Tokiwano et al., Biomimetic construction of fused tricyclic ether by cascaded endo-cyclization of the hydroxy triepoxide, SYNLETT, (3), 2000, pp. 335-338
The biomimetic successive ring-closure reactions of hydroxy di- and triepox
ides catalyzed by La(OTf)(3) to the trans-fused bi- and tricyclic ethers we
re achieved in one pot, respectively.