title: Enantioselective synthesis of highly functionalized dihydrofurans through copper-catalyzed asymmetric formal [3+2] cycloaddition of β-ketoesters with propargylic esters.
abstract: An enantioselective synthesis of highly functionalized dihydrofurans through a copper-catalyzed asymmetric [3+2] cycloaddition of β-ketoesters with propargylic esters has been developed. With a combination of Cu(OTf)2 and a chiral tridentate P,N,N ligand as the catalyst, a variety of 2,3-dihydrofurans bearing an exocyclic double bond at the 2 position were obtained in good chemical yields and with good to high enantioselectivities. The exocyclic double bond can be hydrogenated in a highly diastereoselective fashion to give unusual cis-2,3-dihydrofuran derivatives, thus further enhancing the scope of this transformation.
authors.affiliation: Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023 (China) http://www.asym.dicp.ac.cn; University of Chinese Academy of Sciences, Beijing 100049 (China).
authors.forename: Fu-Lin
authors.initials: FL
authors.lastname: Zhu
authors.forename: Ya-Hui
authors.initials: YH
authors.lastname: Wang
authors.forename: De-Yang
authors.initials: DY
authors.lastname: Zhang
authors.forename: Jie
authors.initials: J
authors.lastname: Xu
authors.forename: Xiang-Ping
authors.initials: XP
authors.lastname: Hu
mesh_terms: D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D003500:Cyclization; D004952:Esters / Q000737:chemistry*; D005663:Furans / Q000138:chemical synthesis* / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D004952:Esters; D005663:Furans; D009942:Organometallic Compounds; C073812:2,3-dihydrofuran; D003300:Copper
keywords: 2,3-dihydrofurans; asymmetric catalysis; copper; cycloadditions; synthetic methods