title: Synthesis of multisubstituted 1,3-butadienes using the ruthenium-catalysed double addition of trimethylsilyldiazomethane to alkynylboronates.
abstract: The ruthenium-catalysed double addition of trimethylsilyldiazomethane to alkynes developed by Dixneuf and co-workers was applied to the synthesis of 2-alkyl- or 2-aryl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,4-bis(trimethylsilyl)-1,3-butadienes by use of alkynylboronates instead of alkynes. Di- and tetrasubstituted 1,3-butadienes were prepared from a 2-boryl-1,4-disilyl-1,3-butadiene, using the Suzuki-Miyaura coupling reaction, iodolysis of the alkenylsilane moieties with N-iodosuccinimide and hydrolysis of the carbon-silicon bonds with trifluoroacetic acid. The same compound was converted also to a bicyclic compound, a trisubstituted 1,3-butadiene and a dienone through the Diels-Alder reaction, oxidation of the alkenylboronate moiety and the Mukaiyama aldol reaction.
authors.affiliation: Graduate School of Materials Science, Japan Advanced Institute of Science and Technology, Asahidai, Nomi, Ishikawa, 923-1292, Japan.
authors.forename: Ryotaro
authors.initials: R
authors.lastname: Morita
authors.forename: Eiji
authors.initials: E
authors.lastname: Shirakawa
authors.forename: Teruhisa
authors.initials: T
authors.lastname: Tsuchimoto
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Kawakami