The yttrium ene-diamido complexes supported by Cp (C 5 H 5 ) and Cp* (C 5 Me 5 ) ligands have been synthesized and characterized. The reactions of the Cp* derivative with the isocyanate ArNCO (Ar = 2,6-iPr 2 C 6 H 3 ) led to the C−C coupling of the ene-diamido ligand with ArNCO, while reaction of the Cp derivative resulted in not only the same C−C coupling but also the C−N coupling of the C−C coupling product with another molecule of ArNCO, demonstrating the unique reactivity of enediamido ligands in rare-earth chemistry. The products have been characterized by X-ray single-crystal analysis.