Synthesis and Characterization of Heteromultinuclear Ni/M Clusters (M = Fe, Ru, W) Including a Paramagnetic (NHC)Ni–WCp*(CO)₃ Heterobinuclear Complex

Abstract

A diverse range of heteromultinuclear NiI/[MCO] clusters (MCO = CpFe­(CO)2, CpRu­(CO)2, Cp*W­(CO)3) supported by an N-heterocyclic carbene ligand have been synthesized by reacting the NiI precursor, [IPrNi­(μ-Cl)]2, with [MCO]− reagents under various conditions. Clusters with Ni2Fe2, NiFe2, Ni2Ru, Ni2Ru2, NiRu2, and Ni2W and NiW cores were all characterized using NMR and IR spectroscopy and X-ray crystallography. The NiI-containing paramagnetic heterobinuclear species IPrNi-Wp* (7) was further characterized by EPR spectroscopy and DFT calculations. Notably, unlike previously studied (NHC)­CuI-[MCO] derivatives, complex 7 was found to coordinate Lewis bases such as 3-chloropyridine to produce (IPr)­(3‑Clpy)­NiWp* (9). Complex 9 further underwent thermolytic C–Cl activation, proposed to involve NHC-free [(3‑Clpy)­Ni­(μ-Wp*)]2 (10), to provide the C-arylated N-heterocyclic carbene product [IPr­(py-3-yl)]+[Cp*WCl2(CO)2]− (11).

2-D Molecular Alloy Ru–M (M = Cu, Ag, and Au) Carbonyl Clusters: Synthesis, Molecular Structure, Catalysis, and Computational Studies

“…Heterometallic complexes and clusters containing polar metal–metal interactions are attracting interest for the activation of small molecules and catalytic applications. − Examples include C–H functionalization, carbonylation, hydrogenation, as well as ammonia-borane dehydrogenation . Like ammonia-borane, alcohols such as iso-propanol also contain at the same time both hydridic-like (C–H) and protic (O–H) hydrogens, suitable for activation via interaction with a polar metal–metal bond.…”

Recent advances in catalytic and electrocatalytic applications of half‐sandwich nickel(0/II) N–heterocyclic carbene complexes

“…heterobinuclear complex 12 was prepared by the reaction of W (CO) 6 solution after UV irradiation in tetrahydrofuran with complex 10 and n-propylmercaptane in the presence of trimethylamine, following the similar procedure reported earlier. 33 Similarly, [CpMn (CO) 3 ] solution (after UV irradiation becomes red color) in tetrahydrofuran at À40 С was added to complex 10 to obtain the halfsandwich Ni-Mn heterobinuclear complex 13 in reasonable yield. The structural characterization through X-ray diffraction technique, complexes 11-13 described the sequential change in the characteristic Ni-S and Ni-C bond distances followed by the establishment of a twolegged piano stool coordination geometry.…”

“…Complex 10 , an NHC, cyclopentadiene, and chlorido, was prepared by the classical nickelation route using nickelocene and 1.3–dimesitylimidazolium chloride, which was further subjected to ligand substitution reaction with n–propylmercaptane and triethylamine and acts as a base in toluene for 48 h at room temperature to obtain complex 11 in 87% yield. Further, the half‐sandwich Ni–W heterobinuclear complex 12 was prepared by the reaction of W (CO) 6 solution after UV irradiation in tetrahydrofuran with complex 10 and n–propylmercaptane in the presence of trimethylamine, following the similar procedure reported earlier 33 . Similarly, [CpMn (CO) 3 ] solution (after UV irradiation becomes red color) in tetrahydrofuran at −40°С was added to complex 10 to obtain the half‐sandwich Ni–Mn heterobinuclear complex 13 in reasonable yield.…”