929688-46-0Relevant academic research and scientific papers
Synthesis and elaboration of the dinuclear iron-imide cluster core [Fe 2(μ-NR)2]2+
Duncan, Jeremiah S.,Zdilla, Michael J.,Lee, Sonny C.
, p. 1071 - 1080 (2007)
The protolysis of mononuclear ferric amide precursors FeCl[N(SiMe 3)2]2(THF) (1) or [FeCl2{N(SiMe 3)2}2]- (2) by primary amines provides, under suitable conditions, an effective route to dinuclear weak-field ferric-imide clusters with [Fe2(μ-NR)2]2+ cores. In the synthesis of known arylimide clusters [Fe2(μ-NAr) 2Cl4]2- (Ar = Ph, p-Tol, Mes) from 2, the counterion has a major effect on selectivity and yield, and the use of quaternary ammonium salts affords a substantial improvement over earlier, Li+-based chemistry. The new tert-butylimide core is obtained by protolysis of 1 with excess tBuNH2 to give crystalline cis-Fe2(μ-NtBu)2Cl2(NH 2tBu)2 (9). Complex 9 can be transformed to other dinuclear species through substitution of the terminal amines by pyridines, PEt3, or chloride, or through protolysis of bridging alkylimides by arylamines, allowing isolation of trans-Fe2(μ- NtBu)2Cl2(DMAP)2 (DMAP = 4-dimethylaminopyridine), cis-Fe2(μ-NtBu) 2Cl2(PEt3)2, [Fe2(μ- NtBu)2Cl4]-, and trans-Fe 2(μ-NPh)2Cl2(NH2Bu)2. The susceptibility of alkyl substituents to β-elimination appears to limit the general applicability of protolytic cluster assembly using alkylamines. The dinuclear clusters have been characterized by X-ray, spectroscopic, and electrochemical analyses.
