34 research outputs found
A monomeric imidazol-2-ylidene-silver(I) chloride complex: Synthesis, structure, and solid state Ag-109 and C-13 CP/MAS NMR characterization
The structure of 1,3-bis(2,4,6-trimethylphenyl)-imidazol-2-ylidene-silver(I) chloride, 1, has been determined to be a monomer with weak head-to-tail H...Cl interactions in the solid state. A multinuclear NMR study using a C-13(carbene) labeled derivative, 1(C-13), exhibits C-13-Ag-107,Ag-109 coupling in solution. Further, the solid state CP/MAS NMR parameters, including the principal components of the chemical shift tensors for both the C-13 and Ag-109 centers, have been determined. With the aid of DFT calculations, the orientation of the chemical shift tensors have been assigned
Reactions of (imidazol-2-ylidene)silver(I) chlorides with group 4 metal containing Lewis acids
The reactivity of the monomeric N-heterocyclic carbene silver(I) complexes, 1,3-bis-(2,4,6-trimethylphenyl)imidazol-2-ylidene-silver(I) chloride ([Ag(IMes)Cl], 1) and 1,3-bis-(4-bromo-2,6-dimethylphenyl)imidazol-2-ylidene-silver(I) chloride ([Ag(IMeSBr)Cl], 2), toward the group 4 metal containing Lewis acids, TiCl4 and (eta(5)-C5H5)ZrCl3](-) in dichloromethane was investigated. Instead of the expected transfer of the A-heterocyclic carbene to the Lewis acidic metal centers with accompanying precipitation of AgCl, chloride transfer occurred leading to the formation of the salts, [Ag(IMeS)(2)](+)[(TiCl3)(2)(mu(2)-Cl)(3)](-)(_) (3) and [Ag(IMes(Br))(2)(+)[{(eta(5)-C5H5)ZrCl}(2)(mu(2)-Cl)(3)(-) (4). The structure of the [Ag(IMes(Br))(2)](+) cation in 4 is significantly distorted in the solid state by interactions between the para-Br atoms of the IMeSBr ligands and chloride ligands of the anions
Synthesis of well-defined N-heterocyclic carbene silver(I) complexes
A series of N-heterocyclic carbene (NHC)AgCl complexes [NHC = SIMes (1), IPr (2), SIPr (3), IPrMe (4), IMe (5), My (6), IAd (7), IsB (8), IDD (9), and TPh (10)] have been synthesized through reaction of the imidazolium chloride salts with Ag2O or by direct metalation of the corresponding imidazol-2-ylidene carbene in the presence of AgCl. All silver(I) complexes [(SIMes)AgCl] (11), [(IPr)AgCl] (12), [(SIPr)AgCl] (13), [(IPrMe)AgCl] (14), [(IMe)AgCl] (15), [(ICy)AgCl] (16), [(IAd)AgCl] (17), [(IsB)AgCl] (18), [(IDD)AgCl] (19), and [(TPh)AgCl] (20) have been spectroscopically and structurally characterized. The structure of these silver complexes is dependent on the halide and the solvent used for the synthesis. Adjusting these parameters has led to the previously reported complex, [(IMes)2Ag](+)[AgC12](-) (21), and to a new silver complex, [(IMes)(2)Ag](+)(2)[Ag4I6](2-) (22).</p
Synthesis of well-defined N-heterocyclic carbene silver(I) complexes
A series of N-heterocyclic carbene (NHC)AgCl complexes [NHC = SIMes (1), IPr (2), SIPr (3), IPrMe (4), IMe (5), My (6), IAd (7), IsB (8), IDD (9), and TPh (10)] have been synthesized through reaction of the imidazolium chloride salts with Ag2O or by direct metalation of the corresponding imidazol-2-ylidene carbene in the presence of AgCl. All silver(I) complexes [(SIMes)AgCl] (11), [(IPr)AgCl] (12), [(SIPr)AgCl] (13), [(IPrMe)AgCl] (14), [(IMe)AgCl] (15), [(ICy)AgCl] (16), [(IAd)AgCl] (17), [(IsB)AgCl] (18), [(IDD)AgCl] (19), and [(TPh)AgCl] (20) have been spectroscopically and structurally characterized. The structure of these silver complexes is dependent on the halide and the solvent used for the synthesis. Adjusting these parameters has led to the previously reported complex, [(IMes)2Ag](+)[AgC12](-) (21), and to a new silver complex, [(IMes)(2)Ag](+)(2)[Ag4I6](2-) (22)