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(μ2-Ga(DDP)) (μ2-ethylene)] (6), and [{{μ2-Ga(DDP)}Ni(ethylene)}2Ni(μ2-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.