title: Nickel-mediated three-component cycloaddition reaction of carboryne, alkenes, and alkynes.
abstract: Transition metal mediated multicomponent cross-coupling reactions are a powerful strategy to assemble complex molecules from very simple precursors in a single operation. This Communication reports a nickel-mediated three-component cycloaddition reaction of carboryne with alkenes and alkynes giving dihydrobenzocarborane derivatives with excellent chemo- and regioselectivity. A reaction mechanism involving sequential alkene and alkyne insertion, followed by reductive elimination, is proposed. The key intermediate of nickelacyclopentane was isolated and confirmed by single-crystal X-ray analyses. This work furnishes a new method for the preparation of substituted dihydrobenzocarboranes that are difficult to obtain by other methods.
authors.affiliation: Department of Chemistry and Center of Novel Functional Molecules, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China.
authors.forename: Zaozao
authors.initials: Z
authors.lastname: Qiu
authors.forename: Zuowei
authors.initials: Z
authors.lastname: Xie