Kumar Pankaj, Lee Yong-Min, Park Young Jun, Siegler Maxime A, Karlin Kenneth D, Nam Wonwoo
†Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, Korea.
‡Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, United States.
J Am Chem Soc. 2015 Apr 8;137(13):4284-7. doi: 10.1021/ja513234b. Epub 2015 Mar 25.
New Co(III)-nitrosyl complexes bearing N-tetramethylated cyclam (TMC) ligands, (12-TMC)Co(III)(NO) (1) and (13-TMC)Co(III)(NO) (2), were synthesized via (TMC)Co(II)(CH3CN) + NO(g) reactions. Spectroscopic and structural characterization showed that these compounds bind the nitrosyl moiety in a bent end-on fashion. Complexes 1 and 2 reacted with KO2/2.2.2-cryptand to produce (12-TMC)Co(II)(NO2) (3) and (13-TMC)Co(II)(NO2) (4), respectively; these possess O,O'-chelated nitrito ligands. Mechanistic studies using (18)O-labeled superoxide ((18)O2(•-)) showed that one O atom in the nitrito ligand is derived from superoxide and the O2 produced comes from the other superoxide O atom. Evidence supporting the formation of a Co-peroxynitrite intermediate is also presented.
通过(TMC)Co(II)(CH3CN) + NO(g)反应合成了带有N-四甲基环胺（TMC）配体的新型钴（III）-亚硝酰配合物(12-TMC)Co(III)(NO)（1）和(13-TMC)Co(III)(NO)（2）。光谱和结构表征表明，这些化合物以弯曲的端基方式结合亚硝酰部分。配合物1和2与KO2/2.2.2-穴醚反应，分别生成(12-TMC)Co(II)(NO2)（3）和(13-TMC)Co(II)(NO2)（4）；它们具有O,O'-螯合的亚硝酸根配体。使用(18)O标记的超氧化物((18)O2(•-))进行的机理研究表明，亚硝酸根配体中的一个O原子来自超氧化物，产生的O2来自另一个超氧化物O原子。还提供了支持形成钴-过氧亚硝酸根中间体的证据。
