Nickel(II) allyl complexes with anionic N-heterocyclic carbene-borate ligands

Heterobimetallic Coinage Metal‐Ruthenium Complexes Supported by Anionic N‐Heterocyclic Carbenes

“…Synthesis of silver(I) and copper(I) WCA-NHC complexes in THF solution. 175.59 (9)°and C58À Cu-Cl2 = 179.18 (10)°, and the coppercarbon bond lengths of 1.877(3) Å (Cu1À C1) and 1.879(3) Å (Cu2À C58) are in the same but slightly shorter range compared to the neutral analogues [(IDipp)CuCl] [23] and [(IMes)CuCl]. [24] Related copper(I) chloride complexes bearing anionic malonate or enolate functionalized anionic N-heterocyclic carbenes have also been reported.…”

“…We first studied the reaction of the lithium carbene complex 1•toluene with one equivalent of silver(I) and copper(I) chloride in THF solution, which afforded the ionic complexes 2•THF and 3 after filtration through Celite® and recrystallization from THF/ n-hexane solution (Scheme 1). Regardless of the 1 : 1 stoichiometry, the reaction with AgCl proceeded with formation of the anionic dicarbene silver complex with a linear CÀ AgÀ C angle of 178.08 (10) The lithium counterion is solvated by four THF molecules and resides in a slightly distorted tetrahedral environment (Figure 2). It is interesting to note that the 13 C NMR spectrum exhibits a nicely resolved doublet of doublets at 183.9 ppm, with coupling constants 1 J C,Ag of 195 and 224 Hz for C carbene bonding to the 107 Ag and 109 Ag nuclei.…”

“…Thus, addition of fluoroboranes afforded so‐called WCA‐NHC systems with a weakly coordinating anionic (WCA) borate moiety such as X=B(C 6 F 5 ) 3 , and the resulting solvated lithium salts [(WCA‐NHC)Li(solv.) n ] ( 1 ) were used as transmetalation reagents for the preparation of late transition metal complexes, for example, Au(I), [7] Rh(I), [8] Ir(I),[ 8 , 9 ] Ni(II), [10] Pd(II), [11] which were preferably used as homogeneous catalysts for applications in nonpolar solvents. Early transition metal cyclopentadienyl‐titanium(IV) and imido‐vanadium(V) complexes were also prepared and used as pre‐catalysts for ethylene copolymerization.…”

N‐Heterocyclic Carbenes Carrying Weakly Coordinating Anions

“…In addition, we found that the vacant coordination site at the nickel(II) atom in complex 14 b can be saturated with strong σ‐donor ligands. Therefore, the addition of carbon monoxide or phosphanes furnished complexes of the general type [(F 5 C 6 ) 3 B‐IDipp]PdL( η 3 ‐C 3 H 5 ) (L=CO, PMe 3 , PMe 2 Ph, PMePh 2 ) [37] …”

“…Therefore, the addition of carbon monoxide or phosphanes furnished complexes of the general type [(F 5 C 6 ) 3 B-IDipp]PdL(η 3 -C 3 H 5 ) (L = CO, PMe 3 , PMe 2 Ph, PMePh 2 ). [37] (Imido)vanadium(V) dichloride complexes containing an anionic N-heterocyclic carbene ligand with a weakly coordinating borate moiety were established in 2016 by Nomura and coworkers in cooperation with our group. The compounds [(F 5 C 6 ) 3 B-IXy]V(NR)Cl 2 (15, R = 1-adamantyl, Ph, Xy) were prepared from the reaction of the lithium salt [(F 5 C 6 ) 3 B-IXy]Li-(toluene) (6 f) with the corresponding V(NR)Cl 3 .…”