title: Osmium catalyzed dihydroxylation of 1,2-dioxines: a new entry for stereoselective sugar synthesis.
abstract: A series of 3,6-substituted 3,6-dihydro-1,2-dioxines were dihydroxylated with osmium tetroxide to furnish 1,2-dioxane-4,5-diols (peroxy diols) in yields ranging from 33% to 98% and with de values not less than 90%. The peroxy diols were then reduced to generate a stereospecific tetraol core with R,R,S,S or "allitol" stereochemistry. The peroxy diols and their acetonide derivatives were also ring-opened with Co(II) salen complexes to give novel hydroxy ketones in 77-100% yield, including the natural sugar psicose. Importantly, preliminary work on the catalytic asymmetric ring-opening of meso-peroxy diols using the Co(II) Jacobsens's catalyst indicates that asymmetric sugar synthesis from 1,2-dioxines is possible.
authors.affiliation: Department of Chemistry, University of Adelaide, South Australia 5005, Australia.
authors.forename: Tony V
authors.initials: TV
authors.lastname: Robinson
authors.forename: Dennis K
authors.initials: DK
authors.lastname: Taylor
authors.forename: Edward R T
authors.initials: ER
authors.lastname: Tiekink