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 rac/meso-(mu-eta(2),eta(2)-C7H12)-{Ni(eta(2),eta(2)-C7H12)}(2) with 2,6-dimethylpyridine (Me(2)py) affords (Me(2)py)Ni(eta(2),eta(2)-C7H12) (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 bridged by two butadiyne ligands. For 1-3 the molecular structures have been determined by X-ray crystallography. (C) 1998 Elsevier Science Ltd. All rights reserved.