title: Chelation-mediated palladium(II)-catalyzed domino Heck-Mizoroki/Suzuki-Miyaura reactions using arylboronic acids: increasing scope and mechanistic understanding.
abstract: A palladium(II)-catalyzed Heck-Mizoroki/Suzuki-Miyaura domino reaction involving metal coordinating dimethylaminoethyl vinyl ethers and a number of electron-rich and electron-deficient arylboronic acids has been developed. Through variation of the temperature and the concentration of the p-benzoquinone (p-Bq) ligand/reoxidant, conditions for the robust and convenient one-pot generation of diarylated-saturated ethers were identified. With the aid of coordination of the dimethylamino group to the arylpalladium intermediate, the otherwise predominant formation of the β-arylated olefin could be reversed. A reaction route involving a chelation-controlled carbopalladation, providing a p-Bq stabilized six-membered palladacycle, followed by transmetalation and reductive elimination is suggested to explain the selective formation of saturated diarylated ether products.
authors.affiliation: Organic Pharmaceutical Chemistry, Department of Medicinal Chemistry, Uppsala Biomedical Center, Uppsala University, P.O. Box 574, SE-751 23 Uppsala, Sweden.
authors.forename: Samir
authors.initials: S
authors.lastname: Yahiaoui
authors.forename: Ashkan
authors.initials: A
authors.lastname: Fardost
authors.forename: Alejandro
authors.initials: A
authors.lastname: Trejos
authors.forename: Mats
authors.initials: M
authors.lastname: Larhed
mesh_terms: D016227:Benzoquinones / Q000737:chemistry; D001897:Boronic Acids / Q000138:chemical synthesis*; D002384:Catalysis; D002614:Chelating Agents / Q000737:chemistry / Q000378:metabolism; D056831:Coordination Complexes / Q000737:chemistry; D004583:Electrons; D004987:Ethers / Q000138:chemical synthesis*; D055772:Green Chemistry Technology; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry; D013237:Stereoisomerism; D014753:Vinyl Compounds / Q000737:chemistry*
chemical_list: D016227:Benzoquinones; D001897:Boronic Acids; D002614:Chelating Agents; D056831:Coordination Complexes; D004987:Ethers; D014753:Vinyl Compounds; C004532:quinone; D010165:Palladium