title: Control of diastereoselectivity for iridium-catalyzed allylation of a prochiral nucleophile with a phosphate counterion.
abstract: We report a highly diastereo- and enantioselective allylation of azlactones catalyzed by the combination of a metallacyclic iridium complex and an optically inactive phosphate anion. The process demonstrates an approach for conducting diastereoselective reactions with prochiral nucleophiles in the presence of metallacyclic allyliridium complexes. The reaction provides access to an array of enantioenriched allylated azlactones containing adjacent tertiary and quaternary carbon centers. Preliminary mechanistic studies suggest that the phosphate and methyl carbonate anions together induce the unusually high diastereoselectivity.
authors.affiliation: Department of Chemistry, University of California, Berkeley, California 94720, USA.
authors.forename: Wenyong
authors.initials: W
authors.lastname: Chen
authors.forename: John F
authors.initials: JF
authors.lastname: Hartwig
mesh_terms: D000478:Alkylation; D000498:Allyl Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D007495:Iridium / Q000737:chemistry*; D007783:Lactones / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000498:Allyl Compounds; D007783:Lactones; D009942:Organometallic Compounds; D010710:Phosphates; D007495:Iridium