title: Metal-free regioselective oxidative biaryl coupling leading to head-to-tail bithiophenes: reactivity switching, a concept based on the iodonium(III) intermediate.
abstract: A new synthetic concept for obtaining unsymmetrical biaryl coupling products by an oxidative method is reported. Our synthetic strategy casts light on the reaction intermediate for switching the reactivity of 3-substituted thiophenes. On the basis of this strategy, a novel direct method for the synthesis of head-to-tail bithiophenes using hypervalent iodine(III) reagents has been developed.
authors.affiliation: College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Morimoto
authors.forename: Nobutaka
authors.initials: N
authors.lastname: Yamaoka
authors.forename: Chieko
authors.initials: C
authors.lastname: Ogawa
authors.forename: Tomofumi
authors.initials: T
authors.lastname: Nakae
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Fujioka
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Dohi
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Kita
mesh_terms: D007455:Iodine / Q000737:chemistry*; D015394:Molecular Structure; D010084:Oxidation-Reduction; D013237:Stereoisomerism; D013876:Thiophenes / Q000138:chemical synthesis* / Q000737:chemistry*
chemical_list: D013876:Thiophenes; D007455:Iodine