Asymmetric synthesis of tetrahydropyrans with competitive [1,2]-phenylsulfanyl (PhS) migrations

摘要

Enantiomerically enriched triols were treated with trimethyl orthoacetate and pyridinium toluene-p-sulfonate to givena mixture of unrearranged THF and rearranged THP; treatment of the product mixture with toluene-p-sulfonic acidnequilibrated the mixture to the THP.