Afshar Raman K, Patra Apurba K, Bill Eckhard, Olmstead Marilyn M, Mascharak Pradip K
Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, USA.
Inorg Chem. 2006 May 1;45(9):3774-81. doi: 10.1021/ic060020n.
An Fe(II) carbonyl complex (PaPy3)Fe(CO) (1) of the pentadentate ligand N,N-bis(2-pyridylmethyl)amine-N-ethyl-2-pyridine-2-carboxamide (PaPy3H, H is the dissociable amide proton) has been synthesized and structurally characterized. This Fe(II) carbonyl exhibits its nu(CO) at 1972 cm(-1), and its 1H NMR spectrum in degassed CD3CN confirms its S = 0 ground state. The bound CO in 1 is not photolabile. Reaction of 1 with an equimolar amount of NO results in the formation of the {Fe-NO}7 nitrosyl (PaPy3)Fe(NO) (2), while excess NO affords the iron(III) nitro complex (PaPy3)Fe(NO2) (5). In the presence of [Fe(Cp)2]+ and excess NO, 1 forms the {Fe-NO}6 nitrosyl (PaPy3)Fe(NO)2 (3). Complex 1 also reacts with dioxygen to afford the iron(III) mu-oxo species {(PaPy3)Fe}2O2 (4). Comparison of the metric and spectral parameters of 1 with those of the previously reported {Fe-NO}6,7 nitrosyls 3 and 2 provides insight into the electronic distributions in the Fe(II)-CO, Fe(II)-NO, and Fe(II)-NO+ bonds in the isostructural series of complexes 1-3 derived from a non-heme polypyridine ligand with one carboxamide group.
已合成并对五齿配体N,N-双(2-吡啶甲基)胺-N-乙基-2-吡啶-2-甲酰胺(PaPy3H，H为可解离的酰胺质子)的铁(II)羰基配合物(PaPy3)Fe(CO)(1)进行了结构表征。该铁(II)羰基配合物在1972 cm(-1)处显示其ν(CO)，其在脱气CD3CN中的1H NMR谱证实其基态为S = 0。配合物1中配位的CO对光不敏感。1与等摩尔量的NO反应生成{Fe-NO}7亚硝酰基(PaPy3)Fe(NO)(2)，而过量的NO则生成铁(III)硝基配合物(PaPy3)Fe(NO2)(5)。在[Fe(Cp)2]+和过量NO存在下，1形成{Fe-NO}6亚硝酰基(PaPy3)Fe(NO)2(3)。配合物1还与氧气反应生成铁(III)μ-氧物种{(PaPy3)Fe}2O2(4)。将1的度量和光谱参数与先前报道的{Fe-NO}6,7亚硝酰基3和2的参数进行比较，有助于深入了解由具有一个甲酰胺基团的非血红素多吡啶配体衍生的配合物1-3同构系列中Fe(II)-CO、Fe(II)-NO和Fe(II)-NO+键中的电子分布。
