title: Ruthenium-Catalyzed Cycloisomerization of 2,2'-Diethynyl- biphenyls Involving Cleavage of a Carbon-Carbon Triple Bond.
abstract: A ruthenium complex catalyzes a new cycloisomerization reaction of 2,2'-diethynylbiphenyls to form 9-ethynylphenanthrenes, thereby cleaving the carbon-carbon triple bond of the original ethynyl group. A metal-vinylidene complex is generated from one of the two ethynyl groups, and its carbon-carbon double bond undergoes a [2+2] cycloaddition with the other ethynyl group to form a cyclobutene. The phenanthrene skeleton is constructed by the subsequent electrocyclic ring opening of the cyclobutene moiety.
authors.affiliation: Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan. mtd@rs.tus.ac.jp.
authors.forename: Takanori
authors.identifier: http://orcid.org/0000-0002-9927-3599
authors.initials: T
authors.lastname: Matsuda
authors.affiliation: Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Kato
authors.affiliation: Department of Synthetic Chemistry and Biological Chemistry, Kyoto University, Katsura, Kyoto, 615-8510, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Goya
authors.affiliation: Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Shimada
authors.affiliation: Department of Synthetic Chemistry and Biological Chemistry, Kyoto University, Katsura, Kyoto, 615-8510, Japan. murakami@sbchem.kyoto-u.ac.jp.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Murakami
keywords: alkynes; cycloisomerization; phenanthrenes; ruthenium; vinylidene ligands