Synthesis and Crystal Structure of a Chelating N-Heterocyclic Carbene Palladium Complex Containing N-(3-Bromopropyl)-N’-thioether di-functionalized Imidazol-2-ylidene

A chelating N-heterocyclic carbene palladium complex (3) containing N-(3-bromopropyl)-N’-thioether di-functionalized imidazol-2-ylidene was synthesized by the direct metalation of N-(3-bromopropyl)-N’-thioether di-functionalized imidazolium bromide (2) with Pd(OAc)₂ in the presence of NaOAc and NaBr at room temperature using CH₂Cl₂ as solvent. The structure was characterized by NMR, HR-MS and X-ray crystallography. The results showed that complex 3 consists of two independent molecules with configuration of S_C, R_S in molecule a, and S_C, S_S in molecule b, respectively. The crystal is triclinic, P1 space group, with a = 8.4815(3), b = 8.6338(3), c = 19.2371(7) Å, V = 1245.66(8) ų, and Z = 2 (at 293(2)K).

A chelating N-heterocyclic carbene palladium complex (3) consists of two independent molecules with configurations of S_C, R_S and S_C, S_S respectively has been synthesized through the direct metalation of the precursor imidazolium bromide (2).