Abstract: Alkenylzirconium (IV) complexes, prepared by hydrozirconation of the corresponding acetylenes with CpzZr (H) CI (Cp= q5-C5H5), can be utilized in conjugate addition to oc, b-rnones, catalyzed by Ni (AcAc) z (AcAc= 2, 4-pentanedionate). No 1.2 addition of the alkenyl group is observed, and no trans-cis isomerization occurs. Conjugate addition of terminal alke-nyls proceeds faster than that of internal alkenyls. The product of ...