tudy on Iron-Thiolate-NO Chemistry and Delocalized-Oxidation State of Nickel Compounds

• Main Authors: Chung Hung Hsieh, 謝忠宏
• Other Authors: Wen Feng Liaw
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/69915074558340716388

碩士 === 國立彰化師範大學 === 化學系 === 91 === Abstract Complexes [PPN]2[Fe(S,S-C6H4)2]2 (1) and [PPN][Fe(C4H8O)(S, S-C6H4)2] (2) were synthesized by reacting the five coordinate sixteen electron [PPN][Fe(CN)(CO)2(S,NH-C6H4)] complex with 1,2-benzene dithiol in a 1:2 ratio in CH2Cl2 and THF solution, respectively. Complexes 1 and 2 can serve as an effective NO trapping agent. [PPN][Fe(NO)(S, S-C6H4)2] (3) was obtained by addition of NO gas to complex 1 or 2 in THF. On the basis of XAS (X-ray Absorption Spectroscopy), the formal oxidation state of the iron and nitric oxide is assigned as FeI and NO+, individually. Trinuclear Fe-NO complexes [Fe3(S, S-C6H4)3(NO)3] (4) and [Fe3(S, S-C6H4)3(NO)3] [PF6] (5) were synthesized via the reaction of complex 3 and [NO][PF6] in the ratio of 1:1 and 1:2, respectively. The FeI and NO+ oxidation state are proposed by the XAS in complex 4. The Fe-Fe bond distances of complex 4 are 2.7259(5) (Fe(1)-Fe(2)), 2.7269(5) (4) (Fe(1)-Fe(3)) and 2.6060 (Fe(2)-Fe(3)) Å。Presumably, the coupling of two unpaired electrons of Fe(2) and Fe(3) in complex 4 results in the total spin of 1/2. The dinitrosyl iron complexes (DNICs) [PPN][Fe(NO)2Se5] (6) and [PPN][Fe(NO)2S5] (8) with a six-membered ring were prepared by the reaction of [PPN][Fe(CO)3(NO)] and SeS2/S8 in THF solution, respectively. Based on the XAS, complexes 6 and 8 are best described as two NO radicals bound to a d7 FeI. On the basis of the L-edge absorption spectroscopy, complexes [Ni(S, S-C6H4)2]—, trans-[Ni(S, NH-C6H4)2]—, trans-[Ni(Se, NH-C6H4)2]— (10) and cis-[Ni(Te, NH-C6H4)2]— are best assigned as a resonance hybrid of NiIII (~854.5 eV) and NiII (~853.5 eV). i.e. [NiIII-bis(o- amidochalcogenophenolated(2-)) and NiII-(o-amidochalcogeno- phenolate(2-)-(o-iminochalcogenobenzosemiquinonate(1-)p-radical))].