Collect. Czech. Chem. Commun. 1999, 64, 1119-1124

Reactions of Zirconacyclopentadienes with Propargyl Halides Leading to (Buta-2,3-dien-1-yl)benzenes

Martin Kotora, Yoshinori Noguchi and Tamotsu Takahashi*

Catalysis Research Center and Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo 060, Japan


The reaction of 1,1-bis(η5-cyclopentadienyl)-1-zirconacyclopenta-2,4-dienes with propargyl halides in the presence of a catalytic or a stoichiometric amount of CuCl afforded benzene derivatives. This reaction involves SN2' type of attack of organocopper intermediate to propargyl halide followed by intramolecular carbometallation, and coupling with the second molecule of propargyl halide.

Keywords: Zirconacyclopentadienes; Allenes; Benzenes; Propargyl chloride; Cyclotrimerization; Alkynes.