title: Palladium-Catalyzed Enantioselective α-Arylation of α-Fluoroketones.
abstract: The transition-metal-catalyzed α-arylation of carbonyl compounds is a widely practiced method for C-C bond formation. Several enantioselective versions of this process have been reported, but intermolecular, enantioselective coupling reactions of aryl electrophiles with α-fluoro carbonyl compounds have yet to be disclosed. We report enantioselective coupling of aryl and heteroaryl bromides and triflates with α-fluoroindanones catalyzed by palladium complexes of a BINOL-derived monophosphine and Segphos, respectively. The enolates were generated directly from α-fluoroindanones in the presence of potassium phosphate base during the reactions. We also report that reactions of α-fluorotetralones occur in high yields and enantioselectivities when conducted with enolates generated by elimination of trifluoroacetate from trifluoromethyl β-diketone hydrates. These reactions were catalyzed by palladium complexes of the commercially available bisphosphine Difluorphos. Thus, the formation of enantioenriched α-aryl-α-fluoroketones can be readily achieved by C-C bond formation when the appropriate palladium catalyst and α-fluoro enolate precursor were used.
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Jiao
authors.affiliation: Department of Chemistry, University of California , Berkeley, California 94720, United States.
authors.forename: Jason J
authors.initials: JJ
authors.lastname: Beiger
authors.affiliation: Department of Chemistry, University of California , Berkeley, California 94720, United States.
authors.forename: Yushu
authors.initials: Y
authors.lastname: Jin
authors.affiliation: Department of Chemistry, University of California , Berkeley, California 94720, United States.
authors.forename: Shaozhong
authors.initials: S
authors.lastname: Ge
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.
authors.forename: Jianrong Steve
authors.initials: JS
authors.lastname: Zhou
authors.affiliation: Department of Chemistry, University of California , Berkeley, California 94720, United States.
authors.forename: John F
authors.initials: JF
authors.lastname: Hartwig
mesh_terms: D002384:Catalysis; D006845:Hydrocarbons, Fluorinated / Q000138:chemical synthesis* / Q000737:chemistry; D007659:Ketones / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D006845:Hydrocarbons, Fluorinated; D007659:Ketones; D010165:Palladium