Two borane-functionalized bidentate phosphine ligands that vary in tether length have been prepared to examine cooperative metal−substrate interactions. Ni(0) complexes react with aryl azides at low temperatures to form structurally unusual κ 2 -(N,N)-N 3 Ar adducts. Warming these adducts affords products of N 2 extrusion and in one case, a Ni-imido compound that is capped by the appended borane. Reactions with 1-azidoadamantane (AdN 3 ) provide a distinct outcome, where a proposed nickel imido intermediate activates the sp 2 C−H bonds of arenes, even in the presence of benzylic C−H sites. Combined experimental and computational mechanistic studies demonstrate that the unique reactivity is a consequence of Lewis-acid-induced polarization of the Ni−NR bond, potentially providing a synthetic strategy for chemoselective reaction engineering.

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The C−C bond formation between C1 molecules plays an important role in chemistry as manifested by the Fischer–Tropsch (FT) process. Serving as models for the FT process, we report here the reactions between a neutral AlI complex (MeNacNac)Al (1, MeNacNac=HC[(CMe)(NDipp)]2, Dipp=2,6‐diisopropylphenyl) and various isocyanides. The step‐by‐step coupling mechanism was studied in detail by low‐temperature NMR monitoring, isotopic labeling, as well as quantum chemical calculations. Three different products were isolated in reaction of 1 with the sterically encumbered 2,6‐bis(benzhydryl)‐4‐Me‐phenyl isocyanide (BhpNC). These products substantiate carbene intermediates. The reaction between 1 and adamantyl isocyanide (AdNC) generated a trimerization product, and a corresponding carbene intermediate could be trapped in the form of a molybdenum(0) complex. Tri‐, tetra‐, and even pentamerization products were isolated with the sterically less congested phenyl and p‐methoxyphenyl isocyanides (PhNC and PMPNC) with concurrent construction of quinoline or indole heterocycles. Overall, this study provides evidence for carbene intermediates in FT‐type chemistry of aluminium(I) and isocyanides.