title: Phosphine-catalyzed [3+2] annulations of γ-functionalized butynoates and 1C,3O-bisnucleophiles: highly selective reagent-controlled pathways to polysubstituted furans.
abstract: In this paper, a reagent-controlled [3+2] annulation of γ-functionalized butynoates 1 and 1C,3O-bisnucleophiles 2 is reported, which leads to three distinct furan skeletons 3-5. A PPh(3) catalyst preferentially attached the β-position of 1a, facilitating α-addition to furnish Type I annulations. With the assistance of Ag(2)O, Type II annulations were achieved via selective γ-substitution. In the absence of the PPh(3) catalyst, the reagent Cs(2)CO(3) promoted β-addition to realize Type III annulations.
authors.affiliation: Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, Meilong Road No. 130, Shanghai, 200237, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Hu
authors.forename: Yabing
authors.initials: Y
authors.lastname: Wei
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Tong
mesh_terms: D002087:Butyrates / Q000737:chemistry*; D002384:Catalysis; D005663:Furans / Q000138:chemical synthesis* / Q000737:chemistry; D007202:Indicators and Reagents; D015394:Molecular Structure; D010165:Palladium; D010720:Phosphines / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D002087:Butyrates; D005663:Furans; D007202:Indicators and Reagents; D010720:Phosphines; D010165:Palladium; C044646:phosphine