title: Visible-Light-Promoted Photocatalytic B-C Coupling via a Boron-Centered Carboranyl Radical: Facile Synthesis of B(3)-Arylated o-Carboranes.
abstract: A visible-light-mediated in situ generation of a boron-centered carboranyl radical (o-C2 B10 H11(.)) has been described. With eosin Y as a photoredox catalyst, 3-diazonium-o-carborane tetrafluoroborate [3-N2-o-C2B10H11][BF4] was converted into the corresponding boron-centered carboranyl radical intermediate, which can undergo efficient electrophilic substitution reaction with a wide range of (hetero)arenes. This general and simple procedure provides a metal-free alternative for the synthesis of 3-(hetero)arylated-o-carboranes.
authors.affiliation: Department of Chemistry and State Key Laboratory of Synthetic, Chemistry, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China.
authors.forename: Da
authors.initials: D
authors.lastname: Zhao
authors.affiliation: Department of Chemistry and State Key Laboratory of Synthetic, Chemistry, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China. zxie@cuhk.edu.hk.
authors.forename: Zuowei
authors.initials: Z
authors.lastname: Xie
keywords: arylation; carborane; heterocycles; photocatalysis; radicals