To further explore the reactivity of the (C₅Me₅)⁻ ligand in the sterically crowded (C₅Me₅)₃M complexes, reactions with PhEEPh (E = S, Se, Te) have been examined. With M = La, Pr, Nd, Sm, and Y, PhSSPh reacts to form the expected reduction products, [(C₅Me₅)₂M(SPh)]₂, but the major organic byproduct is not the sterically induced reduction product, (C₅Me₅)₂. Instead, the sigma bond metathesis product, C₅Me₅SPh, is the major byproduct. In contrast, reactions with (C₅Me₅)₃Ce and (C₅Me₅)₃U gave a mixture of C₅Me₅SPh and (C₅Me₅)₂ as byproducts. PhSSPh reactions with the lanthanide nitrile adducts, (C₅Me₅)₃Ln(NCCMe₃)₂ (Ln = La, Ce) and (C₅Me₅)₃Nd(NCCMe₃), formed [(C₅Me₅)₂Ln(SPh)(NCCMe₃)]₂ and only C₅Me₅SPh as the byproduct. PhSeSePh reactions paralleled the PhSSPh results, but reactions of PhTeTePh with (C₅Me₅)₃La, (C₅Me₅)₃Sm, and (C₅Me₅)₃La(NCCMe₃)₂ gave only (C₅Me₅)₂ as a byproduct.