A hybrid imidazolylidene/imidazolium nickel NHC complex: an isolated intermediate

作者：Altmann Philipp J; Ehrenreich Michael; Poethig Alexander

来源：Acta Crystallographica Section C-Structural Chemistry, 2017, 73(11): 880-+.

DOI：10.1107/S2053229617013250

• N-heterocyclic carbene
• NHC
• transition metal
• crystal structure
• trapped intermediate
• macrocyclic ligand

Macrocyclic ligand systems with a variety of (different) donor sites oftentimes give rise to very exciting and unexpected multinuclear metal complexes. We report herein the structure of a trinuclear mixed imidazolylidene/imidazolium nickel N-heterocyclic carbene (NHC) complex, namely di-mu-chlorido-bis{mu-calix[2]imidazolium[2] imidazolylidene[2]pyrazolate}trinickel(II)tetrakis(hexafluoridophosphate) acetonitrile tetrasolvate, [Ni-3(C24H24N12)(2)Cl-2](PF6)(4)center dot 4CH(3)CN or [Ni-3(L Me)(2)Cl-2](PF6)(4)center dot 4CH(3)CN, that can be understood as a trapped reaction intermediate during the synthesis of the respective [Ni2L Me](PF6)(2) product. The structure not only contains protonated next to deprotonated imidazole heterocycles, but also Ni2+ ions with fundamentally different coordination modes within one molecule. Two of the three metal atoms are coordinated in a square-pyramidal fashion by half a ligand molecule and one chloride ligand, whereas the third Ni2+ ion is bound octahedrally by four pyrazolate moieties and two chloride anions.

• 出版日期2017-11