The terminal zirconium chalcogenido complexes Cp 2 *Zr(E)(NC 5H 5)(Cp * = η 5-C 5Me 5; E = O, S, Se, Te) are conveniently synthesized by the reactions of Cp 2 *Zr(CO) 2 with either N 2O or the elemental chalcogen (S, Se, Te) in the presence of pyridine. The [Zr=E] functionalities in these complexes are highly reactive and undergo a variety of 1,2-addition and cycloaddition reactions, resulting in a diverse array of products. For example, reactions of the zirconium oxo complex Cp 2 *Zr(O)(NC 5H 5) yield Cp 2 *Zr(OH) 2, Cp 2 *Zr( η 2-O 2CMe)( η 1-OCOMe), Cp 2 *Zr(OPh) 2, Cp 2 *Zr(OH)(NH 2), Cp 2 *Zr(OH)(NHPh), Cp 2 *Zr(OH)[ η 2-N(Ph)NH 2], Cp 2 *Zr(H)(OSiH 2Ph), [Cp 2 *Zr(H)]( μ-O)[Cp 2 *Zr(OH)], Cp 2 *Zr(OH)[ η 1-OC(R)=CH 2] (R = Me, Ph, Bu t), Cp 2 *Zr(OH)I, Cp 2 *Zr(OMe)I, Cp 2 *Zr(OSiMe 3)Cl, Cp 2 *Zr[ η 2-OCH(R)OCH(R)O] (R = H, Pr i, Bu t), and Cp 2 *Zr[ η 2-OC(Ph)NC(Ph)N].