Nickel olefin complexes supported by Gaⁱ(DDP)

The reactions of the low-valent group 13 bis-imidinate ligand Ga(DDP) [DDP = 2-{(2,6-diisopropylphenyl)amino}-4-{(2,6-diisopropylphenyl)imino}-2-pentene] with Ni(0) olefin complexes are reported. Treatment of [Ni(cdt)] (cdt = 1,5,9-cyclododecatriene) with Ga(DDP) yields the adduct [(cdt)Ni{Ga(DDP)}] (1). Substitution of the cdt moiety in 1 with olefins (ethylene, styrene, or dvds (dvds = 1,3-divinyl-(1,1,3,3-tetramethyl)disiloxane)) gives a series of olefin complexes, i.e., [{(DDP)Ga}Ni(C₂H₄)₂] (2), [(DDP)GaNi(styrene)₂] (3), and [{(DDP)Ga}Ni(dvds)] (4). The reaction of Ga(DDP) with excess [Ni(C₂H₄)₃] yields the clusters [{(ethylene)₂Ni}₂(μ²-Ga(DDP)] (5), [{(ethylene)Ni}₂(a²-Ga(DDP)) (μ²-ethylene)] (6), and [{{μ²-Ga(DDP)}Ni(ethylene)}₂Ni(μ ²-CH=CH₂)(H)] (7). While an agostic interaction of a bridging ethylene molecule is observed in 5 and 6, a C-H activation takes place in the formation of 7. Finally, the reaction of [Ni(cod)₂] (cod = 1,5-cyclooctadiene) with Ga(DDP) in the presence of Ph-C≡C-Ph yields the dimeric complex [{{μ²-Ga(DDP)}Ni₂(μ²- PhCCPh)}₂(PhCCPh)(1,5-cod)] (8). Compounds 1-8 were fully characterized by C/H analysis, NMR spectroscopy, and X-ray single-crystal diffraction studies.