title: Diastereoselective reductive ring expansion of spiroketal dihydropyranones to cis-fused bicyclic ethers.
abstract: A novel double cascade synthetic strategy was developed for the diastereoselective syntheses of cis-fused bicyclic ethers, featuring cascade Achmatowicz rearrangement/spiroketalization and cascade spiroketal reduction/oxa-Michael cyclization. Especially, the chemo-, regio-, and diastereoselective reduction of densely functionalized spiroketal dihydropyranones, followed by oxa-Michael cyclization in a one-pot fashion, was achieved.
authors.affiliation: Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
authors.forename: Liangyu
authors.initials: L
authors.lastname: Zhu
authors.forename: Liyan
authors.initials: L
authors.lastname: Song
authors.forename: Rongbiao
authors.initials: R
authors.lastname: Tong