Reaction of Li[HC(NDep)2](THF)2 (Dep = 2,6-diethylphenyl) with 1 equivalent of NiI2 afforded Ni2(η1-I)(μ-I)[LiI(THF)3][μ-HC(NDep)2]2 (2). When the amount of NiI2 was reduced by half an equivalent, a lantern- type dinickel complex, Ni2[(μ-HC(NDep)2)]3 (4), was obtained instead. Treatment of 2 with 3 equivalents of Li[HC(NDep)2](THF)2 at 90 ℃ also gave 4. KC8 reduction of 2 resulted in the isolation of (μ-I)[Ni(μ-HC(NDep)2)(THF)]2 (3) and [Ni(μ-HC(NDep)2)]2 (5). The low-valent and low-coordinate dinickel complex [Ni(μ-HC(NDipp)2)]2 (Dipp = 2,6-diisopropylphenyl) (1c) displays interesting reactivity toward several small molecules. Exposure of solution 1c to nitric oxide led to the isolation of [Ni(μ-HC(NDipp)2)(NO)]2 (6). 1c reacted with elemental sulfur and selenium to furnish (μ3-S)2{Ni[μ-HC(NDipp)2(S)]}3 (7) and Ni{[(μ-κ1:κ2-Se2)(μ-Se)]{Ni[μ-HC(NDipp)2(Se)]}2}2 (8), respectively. Reaction of 1c with P4 afforded {Ni2[μ-HC(NDipp)2][μ-P4HC(NDipp)2]}2 (9).
On the other hand, the inverted-sandwiched dichromium complex, (μ-η6:η6-C7H8)[Cr(Nacnac)Dipp]2 ((Nacnac)Dipp = HC[C(Me)N-2,6-iPr2- C6H3]2), reacted with DIBALH (diisobutylaluminium hydride) to give rise to the formation of a dinuclear chromium hydride complex
[(μ-H)Cr(Nacnac)Dipp]2 (10). When (μ-η6:η6-C7H8)[Cr(Nacnac)Dipp]2 was treated with BH3NH3, a borazine-bridged complex, (μ-η6:η6-B3N3H6)[Cr(Nacnac)Dipp]2 (11), was isolated. Moreover, reaction of (μ-η6:η6-C7H8)[Cr(Nacnac)Dipp]2 with BH3NMe2H engendered the formation of a σ-borane complex [η3-B(µ-NMe2)(µ-H)H2]Cr(Nacnac)Dipp (12). Reactions of (μ-η6:η6-C7H8)[Cr(Nacnac)Dipp]2 with BH3NMe3, BH3NH2iPr and BH3NH2(Dipp) all led to the isolation of bis-σ-borane complex [η3-B(µ-H)2H2]Cr(Nacnac)Dipp (13).
Addtionally, reaction of the inverted-sandwiched dinickel complex, (μ-η3:η3-C7H8)[Ni(Nacnac)Dipp]2, with COT (1,3,5,7-cyclooctatetraene) produced (μ-κ3:κ3-C16H16)[Ni(Nacnac)Dipp]2 (14), which is formed via a C-C bond coupling of two molecules of COT.

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