title: Ruthenium-catalyzed cycloaddition of 1,6-diynes with isothiocyanates and carbon disulfide: first transition-metal catalyzed [2 + 2 + 2] cocyclotrimerization involving C=S double bond.
abstract: In the presence of 10 mol % Cp*Ru(cod)Cl, 1,6-diynes with a tertiary center at 4-position reacted with various isothiocyanates at their C=S double bond to afford bicyclic (2H)-thiopyranimines in 35-88% yields. The (2H)-thiopyran structure was unequivocally determined by X-ray analysis. The cycloaddition of carbon disulfide with a diyne similarly gave the expected bicyclic dithiopyrone in 50% yield.
authors.affiliation: Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603, Japan.
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Takagishi
authors.forename: Kenji
authors.initials: K
authors.lastname: Itoh