Ruthenium-Catalyzed Cycloisomerization of 2,2'-Diethynyl- biphenyls Involving Cleavage of a Carbon-Carbon Triple Bond

Takanori Matsuda; Kotaro Kato; Tsuyoshi Goya; Shingo Shimada; Masahiro Murakami

doi:10.1002/chem.201504937

Ruthenium-Catalyzed Cycloisomerization of 2,2'-Diethynyl- biphenyls Involving Cleavage of a Carbon-Carbon Triple Bond

Chemistry. 2016 Feb;22(6):1941-1943. doi: 10.1002/chem.201504937. Epub 2016 Jan 8.

Authors

Takanori Matsuda¹, Kotaro Kato², Tsuyoshi Goya³, Shingo Shimada², Masahiro Murakami⁴

Affiliations

¹ Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan. [email protected].
² Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan.
³ Department of Synthetic Chemistry and Biological Chemistry, Kyoto University, Katsura, Kyoto, 615-8510, Japan.
⁴ Department of Synthetic Chemistry and Biological Chemistry, Kyoto University, Katsura, Kyoto, 615-8510, Japan. [email protected].

PMID: 26660656
DOI: 10.1002/chem.201504937

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.

Keywords: alkynes; cycloisomerization; phenanthrenes; ruthenium; vinylidene ligands.