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Hydrogenation reactions of alkenes were catalyzed by zirconium–alkene complex derivatives which were prepared from Cp2ZrCl2 (Cp = η5-C5H5) and n equiv. of RR′CHCH2M (M = MgX or Li). By the use of three or more equiv. of EtMgBr relative to Cp2ZrCl2, the product yield of hydrogenation of 1-decene was remarkably improved most likely due to the stabilization of the Zr(II) species.

Addition of one equivalent of RCH2CH2MgX to Cp2ZrMe2 (Cp = C5H5) in the presence of PMe3 led to a transmetalation reaction to afford zirconocene-alkene complexes Cp2Zr(RCH=CH2)(PMe3) in good yields along with the formation of MeMgX.

Reactions of zirconocene-alkene complexes with aldehydes gave alcohols as coupling products after hydrolysis. The carbon-carbon bond formation proceeded at C1 carbon of alkenes, in sharp contrast to the reactions of alkene-alkene coupling on zirconium. A similar alcohol was also obtained by the reaction of zirconacyclopentane with aldehyde after hydrolysis. Treatment of (C5Me5)2ZrEt2 with styrene gave 2-phenylbutane after hydrolysis contrary to the case of Cp2ZrEt2 which afforded 1-phenylbutane.

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