title: Single-electron-transfer-induced coupling of arylzinc reagents with aryl and alkenyl halides.
abstract: Arylzinc reagents, prepared from aryl halides/zinc powder or aryl Grignard reagents/zinc chloride, were found to undergo coupling with aryl and alkenyl halides without the aid of transition-metal catalysis to give biaryls and styrene derivatives, respectively. In this context, we have already reported the corresponding reaction using aryl Grignard reagents instead of arylzinc reagents. Compared with the Grignard cross-coupling, the present reaction features high functional-group tolerance, whereby electrophilic groups such as alkoxycarbonyl and cyano groups are compatible as substituents on both the arylzinc reagents and the aryl halides. Aryl halides receive a single electron and thereby become activated as the corresponding anion radicals, which react with arylzinc reagents, thus leading to the cross-coupling products.
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo, Kyoto, 606-8502 (Japan). shirakawa@kuchem.kyoto-u.ac.jp.
authors.forename: Eiji
authors.initials: E
authors.lastname: Shirakawa
authors.forename: Fumiko
authors.initials: F
authors.lastname: Tamakuni
authors.forename: Eugene
authors.initials: E
authors.lastname: Kusano
authors.forename: Nanase
authors.initials: N
authors.lastname: Uchiyama
authors.forename: Wataru
authors.initials: W
authors.lastname: Konagaya
authors.forename: Ryo
authors.initials: R
authors.lastname: Watabe
authors.forename: Tamio
authors.initials: T
authors.lastname: Hayashi
keywords: C-C coupling; anion radicals; aromatic compounds; biaryls; single-electron transfer