title: Ring-expansion protocol: preparation of synthetically versatile dihydrotropones.
abstract: A ring-expansion protocol that consisted of the 1,2-addition of various enolate nucleophiles to 6-trimethylsiloxy-2-cyclohexene-1-one (1) and the NaIO(4)-promoted oxidative ring opening of the resulting diols 2, followed by an intramolecular Knoevenagel condensation, furnished versatile dihydrotropones 6. Maintaining Z-configuration in the oxidative ring-opening products 3 is crucial for the success of the ring-expansion strategy. Dihydrotropones 6 are ripe for further elaborations such as oxidation to tropones 8 and Diels-Alder reaction with the Danishefsky's diene 10 to afford polycyclic compounds 12.
authors.affiliation: Department of Nano Science and Engineering, Myong Ji University, Yongin, Kyunggi-Do 449-728, Korea.
authors.forename: Young-Sun
authors.initials: YS
authors.lastname: Do
authors.forename: Ruiying
authors.initials: R
authors.lastname: Sun
authors.forename: Hee Jin
authors.initials: HJ
authors.lastname: Kim
authors.forename: Jung Eun
authors.initials: JE
authors.lastname: Yeo
authors.forename: Sung-Hee
authors.initials: SH
authors.lastname: Bae
authors.forename: Sangho
authors.initials: S
authors.lastname: Koo
mesh_terms: D006018:Glycols / Q000737:chemistry; D010084:Oxidation-Reduction; D013237:Stereoisomerism; D014334:Tropolone / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry
chemical_list: D006018:Glycols; D014334:Tropolone; C003730:tropone