title: Highly Regioselective Synthesis of Substituted IsoindolinonesviaRuthenium-Catalyzed Alkyne Cyclotrimerizations.
abstract: (Cyclooctadiene)(pentamethylcyclopentadiene)ruthenium chloride [Cp*RuCl(cod)] has been used to catalyze the regioselective cyclization of amide-tethered diynes with monosubstituted alkynes to give polysubstituted isoindolinones. Notably, the presence of a trimethylsilyl group on the diyne generally led to complete control over the regioselectivity of the alkyne cyclotrimerization. The cyclization reaction worked well in a sustainable non-chlorinated solvent and was tolerant of moisture. The optimized conditions were effective with a diverse range of alkynes and diynes. The 7-silylisoindolinone products could be halogenated, protodesilylated or ring opened to access a range of usefully functionalized products.
authors.affiliation: Department of Chemistry, University College London, Christopher Ingold Laboratories London, WC1H 0AJ, U.K. ; phone: (+44)-(0)20-7679-2467.
authors.forename: Robert W
authors.initials: RW
authors.lastname: Foster
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Tame
authors.forename: Helen C
authors.initials: HC
authors.lastname: Hailes
authors.forename: Tom D
authors.initials: TD
authors.lastname: Sheppard
keywords: alkynes; amide tether; cyclotrimerization; isoindolinones; ruthenium; trimethylsilyl group