title: Protecting-Group-Free Enantioselective Synthesis of (-)-Pallavicinin and (+)-Neopallavicinin.
abstract: The first enantioselective synthesis of (-)-pallavicinin and (+)-neopallavicinin has been achieved in 15 steps. The described synthesis avoids protecting-group manipulations by synthesis designs predicated on highly chemo- and stereoselective transformations. Highlights of the synthesis include a palladium-catalyzed enantioselective decarboxylative allylation to form the chiral all-carbon quaternary stereocenter, a palladium-catalyzed oxidative cyclization to assemble the [3.2.1]-bicyclic moiety, and an unprecedented LiBHEt3-induced fragmentation/protonation of an α-hydroxy epoxide to form the α-furan ketone with the desired configuration.
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Xue Yuan Rd. 38, Beijing 100191 (China).
authors.forename: Bin
authors.initials: B
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Xue Yuan Rd. 38, Beijing 100191 (China).
authors.forename: Lei
authors.initials: L
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Xue Yuan Rd. 38, Beijing 100191 (China). yxjia@bjmu.edu.cn.|State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032 (China). yxjia@bjmu.edu.cn.
authors.forename: Yanxing
authors.initials: Y
authors.lastname: Jia
mesh_terms: D006576:Heterocyclic Compounds, 4 or More Rings / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D006576:Heterocyclic Compounds, 4 or More Rings; C423331:pallavicinin
keywords: epoxidation; natural products; palladium; terpenoids; total synthesis