Hydrosilylation reactions between dimethylsilyl- and 1,1'-bis(dimethylsilyl)ferrocene; dimethylsilyl- and 1,1'-bis(dimethylsilyl)troticene {troticene = η-cyclopentadienyl(η-cycloheptatrienyl)titanium}; dimethylsilyl- and 1,4-bis(dimethylsilyl)benzene and selected terminal alkynes were performed and the product distributions analyzed. In all cases, mixtures of α- and β(E)- isomers were formed. In general β(E)- isomers are preferred, however in the cases of the disubstituted metallocene complexes the the α isomers predominate. The selectivity is rationalized based upon the unique geometry constraints of the metallocene derivatives.