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The first nickel-catalyzed N-arylation of amides with (hetero)aryl (pseudo)halides employing an organic amine base is described. By using a bis(cyclooctadienyl)nickel/8-[2-(dicyclohexylphosphinyl)phenyl]-1,3,5,7-tetramethyl-2,4,6-trioxa-8-phosphaadamantane catalyst mixture in combination with DBU/NaTFA as a dual-base system, a diversity of (hetero)aryl chloride, bromide, tosylate, and mesylate electrophiles were successfully cross-coupled with structurally diverse primary amides, as well as a selection of secondary amide, lac­tam, and oxazolidone nucleophiles.

4-Amino-1,8-naphthalimides, potentially useful fluorescent probes in biological applications, are prepared via Ni(cod)

The base metal-catalyzed C-N cross-coupling of bulky α,α,α-trisubstituted primary alkylamines with (hetero)aryl electrophiles represents a challenging and under-developed class of transformations that is of significant potential utility, including in the synthesis of lipophilic active pharmaceutical ingredients. Herein, we report that a new, air-stable Ni(II) pre-catalyst incorporating the optimized ancillary ligand PhPAd-DalPhos enables such transformations of (hetero)aryl chloride, bromide, and tosylate electrophiles to be carried out for the first time with substrate scope rivalling that achieved using state-of-the-art Pd catalysts, including room temperature cross-couplings of (hetero)aryl chlorides that are unprecedented for any catalyst (Pd, Ni, or other).

We report herein on the results of our combined experimental/computational study regarding the catalytic performance of PAd-DalPhos (L1) in nickel-catalyzed ammonia arylation for primary aniline synthesis. Primary arylamine C–N reductive eliminations occurring from arylnickel(II) parent amido complexes of the type (L)Ni(Ph)(NH2) were modeled by use of density-functional theory (DFT) methods, for a series of L1 derivatives. The dual aims were to assess the effect of structural modifications to L1 on potentially rate-limiting C–N reductive elimination and to identify promising candidates for experimental inquiry. Increasing the steric demand of the Paryl groups from o-tolyl (in L1) to mesityl (in L16) resulted in a significant lowering of the barrier to C–N reductive elimination (ΔG⧧RE), which can be attributed in part to interactions between the ligand Paryl groups and the nickel-bound amido ligand, as observed in noncovalent interaction (NCI) plots of the reductive elimination transition-state structures....

The use of (L)Ni(o-tolyl)Cl precatalysts (L = PAd-DalPhos or CyPAd-DalPhos) enables the C(sp2)–O cross-coupling of primary, secondary, or tertiary aliphatic alcohols with (hetero)aryl electrophiles, including unprecedented examples of such nickel-catalyzed transformations employing (hetero)aryl chlorides, sulfonates, and pivalates. In addition to offering a competitive alternative to palladium catalysis, this work establishes the feasibility of utilizing ancillary ligation as a complementary means of promoting challenging nickel-catalyzed C(sp2)–O cross-couplings, without recourse to precious-metal photoredox catalytic methods.