PYRIDINE-BASED MONO(LIGAND)NICKEL(0) COMPLEXES OF 1,6-HEPTADIENE, 1-PHENYL-2-TRIMETHYLSILYL-ACETYLENE, AND 1,4-BIS(TRIMETHYLSILYL)-1,3-BUTADIYNE

The reaction of -eta(2),eta(2)-C7H12)-{Ni(eta(2),eta(2)-C7H12)}(2) wit h 2,6-dimethylpyridine (Me(2)py) affords (Me(2)py)Ni(eta(2),eta(2)-C7H 12) (1). Complex 1 serves as precursor for the preparation of the Ni(O )-bis(alkyne) complexes (Me(2)py)Ni(eta(2)-PhC drop CSiMe3)(2) (2) and {(Me(2)py)Ni}(2)(mu-eta(2),eta(2)-Me3SiC drop C-C drop CSiMe3)(2) (3) . The latter is the first complex in which two metal centers are bridg ed by two butadiyne ligands. For 1-3 the molecular structures have bee n determined by X-ray crystallography. (C) 1998 Elsevier Science Ltd. All rights reserved.