title: Dehydrative C-H/N-OH functionalizations in H2O by ruthenium(II) catalysis: subtle effect of carboxylate ligands and mechanistic insight.
abstract: A ruthenium(II) complex derived from the electron-deficient aromatic carboxylic acid 3-(F3C)C6H4CO2H proved to be a highly efficient catalyst for dehydrative alkyne annulation by NH-free hydroxamic acids in water. The C-H/N-OH functionalization occurred with excellent positional selectivity as well as ample substrate scope, setting the stage for effective intermolecular alkenylations of hydroxamic acids. Detailed mechanistic studies were suggestive of a kinetically relevant C-H metalation by carboxylate assistance along with subsequent migratory alkyne insertion, reductive elimination, and intramolecular oxidative addition.
authors.affiliation: Institut für Organische und Biomolekulare Chemie, Georg-August-Universität , Tammannstrasse 2, 37077 Göttingen, Germany.
authors.forename: Fanzhi
authors.initials: F
authors.lastname: Yang
authors.forename: Lutz
authors.initials: L
authors.lastname: Ackermann
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D002264:Carboxylic Acids / Q000737:chemistry*; D002384:Catalysis; D056831:Coordination Complexes / Q000737:chemistry*; D006877:Hydroxamic Acids / Q000737:chemistry*; D008024:Ligands; D015394:Molecular Structure; D010084:Oxidation-Reduction; D012428:Ruthenium / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D000480:Alkynes; D002264:Carboxylic Acids; D056831:Coordination Complexes; D006877:Hydroxamic Acids; D008024:Ligands; D014867:Water; D012428:Ruthenium