title: A metalloenzyme-like catalytic system for the chemoselective oxidative cross-coupling of primary amines to imines under ambient conditions.
abstract: The direct oxidative cross-coupling of primary amines is a challenging transformation as homocoupling is usually preferred. We report herein the chemoselective preparation of cross-coupled imines through the synergistic combination of low loadings of Cu(II) metal-catalyst and o-iminoquinone organocatalyst under ambient conditions. This homogeneous cooperative catalytic system has been inspired by the reaction of copper amine oxidases, a family of metalloenzymes with quinone organic cofactors that mediate the selective oxidation of primary amines to aldehydes. After optimization, the desired cross-coupled imines are obtained in high yields with broad substrate scope through a transamination process that leads to the homocoupled imine intermediate, followed by dynamic transimination. The ability to carry out the reactions at room temperature and with ambient air, rather than molecular oxygen as the oxidant, and equimolar amounts of each coupling partner is particularly attractive from an environmentally viewpoint.
authors: UMR 8638 CNRS-Université Paris Descartes (Paris 5), Sorbonne Paris Cité, Faculté de Pharmacie de Paris, 4 avenue de l'Observatoire, 75270 Paris cedex 06 (France). martine.largeron@parisdescartes.fr.
authors: Martine
authors: M
authors: Largeron
authors: Maurice-Bernard
authors: MB
authors: Fleury
mesh_terms: D000447:Aldehydes / Q000737:chemistry; D000588:Amines / Q000737:chemistry*; D002384:Catalysis; D003300:Copper / Q000737:chemistry; D007097:Imines / Q000737:chemistry*; D008667:Metalloproteins / Q000737:chemistry*; D015394:Molecular Structure; D010084:Oxidation-Reduction; D011809:Quinones / Q000737:chemistry
chemical_list: D000447:Aldehydes; D000588:Amines; D007097:Imines; D008667:Metalloproteins; D011809:Quinones; C116897:iminoquinone; D003300:Copper
keywords: cross-coupling; cycloaddition; homogeneous catalysis; oxidation; primary amines