title: A Catalytic Asymmetric Total Synthesis of (-)-Perophoramidine.
abstract: We report a catalytic asymmetric total synthesis of the ascidian natural product perophoramidine. The synthesis employs a molybdenum-catalyzed asymmetric allylic alkylation of an oxindole nucleophile and a monosubstituted allylic electrophile as a key asymmetric step. The enantioenriched oxindole product from this transformation contains vicinal quaternary and tertiary stereocenters, and is obtained in high yield along with high levels of regio-, diastereo-, and enantioselectivity. To install the second quaternary stereocenter in the target, the route utilizes a novel regio- and diastereoselective allylation of a cyclic imino ether to deliver an allylated imino ether product in near quantitative yield and with complete regio- and diastereocontrol. Oxidative cleavage and reductive amination are used as final steps to access the natural product.
authors.affiliation: Department of Chemistry, Stanford University Stanford, CA 94305-5580 (USA).
authors.forename: B M
authors.initials: BM
authors.lastname: Trost
authors.affiliation: Department of Chemistry, Stanford University Stanford, CA 94305-5580 (USA).
authors.forename: M
authors.initials: M
authors.lastname: Osipov
authors.affiliation: Department of Chemistry, Stanford University Stanford, CA 94305-5580 (USA).
authors.forename: S
authors.initials: S
authors.lastname: Krüger
authors.affiliation: Department of Chemistry, Stanford University Stanford, CA 94305-5580 (USA).
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang