title: Studying regioisomer formation in the Pd-catalyzed fluorination of aryl triflates by deuterium labeling.
abstract: Isotopic labeling has been used to determine that a portion of the desired product in the Pd-catalyzed fluorination of electron-rich, non-ortho-substituted aryl triflates results from direct C-F cross-coupling. In some cases, formation of a Pd-aryne intermediate is responsible for producing undesired regioisomers. The generation of the Pd-aryne intermediate occurs primarily via ortho-deprotonation of a L·Pd(Ar)OTf (L = biaryl monophosphine) species by CsF and thus competes directly with the transmetalation step of the catalytic cycle. Deuterium labeling studies were conducted with a variety of aryl triflates.
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.
authors.forename: Phillip J
authors.initials: PJ
authors.lastname: Milner
authors.forename: Tom
authors.initials: T
authors.lastname: Kinzel
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Buchwald
mesh_terms: D002384:Catalysis; D003903:Deuterium / Q000737:chemistry*; D005461:Fluorine / Q000737:chemistry*; D007553:Isotope Labeling; D010165:Palladium / Q000737:chemistry*
chemical_list: D005461:Fluorine; D010165:Palladium; D003903:Deuterium