Arene C-H Amination at Nickel in Terphenyl-Diphosphine Complexes with Labile Metal-Arene Interactions

作者：Herbert David E; Lara Nadia C; Agapie Theodor^*

来源：Chemistry - A European Journal, 2013, 19(48): 16453-16460.

DOI：10.1002/chem.201302539

• amination
• arenes
• CH activation
• group transfer
• insertion reactions

The meta-terphenyl diphosphine, m-P-2, 1, was utilized to support Ni centers in the oxidation states 0, I, and II. A series of complexes bearing different substituents or ligands at Ni was prepared to investigate the dependence of metal-arene interactions on oxidation state and substitution at the metal center. Complex (m-P-2)Ni (2) shows strong Ni-0-arene interactions involving the central arene ring of the terphenyl ligand both in solution and the solid state. These interactions are significantly less pronounced in Ni-0 complexes bearing L-type ligands (2-L: L=CH3CN, CO, Ph2CN2), (NiX)-X-I complexes (3-X: X=Cl, BF4, N-3, N3B(C6F5)(3)), and [(m-P-2)(NiCl2)-Cl-II] (4). Complex 2 reacts with substrates, such as diphenyldiazoalkane, sulfur ylides (Ph2SCH2), organoazides (RN3: R=para-C6H4OMe, para-C6H4CF3, 1-adamantyl), and N2O with the locus of observed reactivity dependent on the nature of the substrate. These reactions led to isolation of an (1)-diphenyldiazoalkane adduct (2-Ph2CN2), methylidene insertion into a NiP bond followed by rearrangement of a nickel-bound phosphorus ylide (5) to a benzylphosphine (6), Staudinger oxidation of the phosphine arms, and metal-mediated nitrene insertion into an arene CH bond of 1, all derived from the same compound (2). Hydrogen-atom abstraction from a Ni-I-amide (9) and the resulting nitrene transfer supports the viability of Ni-imide intermediates in the reaction of 1 with 1-azido-arenes.

• 出版日期2013-11-25