The first example of this class of compounds was accidentally synthesized by Kealy and Pauson while trying to make fulvalene. Jerome Maynadie used acetonitrile to convert the bent type of them into the first linear type with an f-element, and types of these compounds containing an intramolecular bridge between two of its components are dubbed the ansa variety. These compounds are often named for Kaminsky when combined with a methyl-alumin-oxane promoter, in which form they can catalyze reactions via the same mechanism as Ziegler-Natta catalysts to create olefin polymers of specific tacticity. Often containing zirconium or iron, FTP identify these compounds that consist of two cyclo- penta-di-enyl ligands bound to a 
The first example of this class of compounds was accidentally synthesized by Kealy and Pauson while trying to make fulvalene. Jerome Maynadie used acetonitrile to convert the bent type of them into the first linear type with an f-element, and types of these compounds containing an intramolecular bridge between two of its components are dubbed the ansa variety. These compounds are often named for Kaminsky when combined with a methyl-alumin-oxane promoter, in which form they can catalyze reactions via the same mechanism as Ziegler-Natta catalysts to create olefin polymers of specific tacticity. Often containing zirconium or iron, FTP identify these compounds that consist of two cyclo- penta-di-enyl ligands bound to a central transition metal ion in a sandwich- like manner, whose prototypical example is ferrocene.
The first example of this class of compounds was accidentally synthesized by Kealy and Pauson while trying to make fulvalene.
{metallocene}s