| Summary: | 博士 === 國立臺灣科技大學 === 應用科技研究所 === 104 === We studied the nitrite reduction and NO transfer between O-bound nitrito coordinated [PPN][Fe(NO)2(ONO)2] and iron N-confused porphyrin center. The nitrite reduction reaction activities converts iron(II) and iron(III) N-confused porphyrin complexes to [Fe(HCTPP)(NO)], [Fe(CTPP)(NO)], or [Fe(CTPPO)(NO)]. Under a 2:1 iron porphyrin/DNIC mole ratio, using 15N isotope labelled [PPh3] [Fe(NO)2(O15NO)2] as the starting DNIC, a 1:1 mixture of [Fe(CTPP)(14NO)] and [Fe(CTPP)(15NO)] are obtained while the DNIC transformed into [PPh3][Fe(14NO)(15NO2)Br2], suggesting that one equivalent of nitrite reduction and one equivalent of direct NO transformation have occurred. NO has found to transfer and coordinate to the axial position of iron(II) N-confused porphyrin center with the release of a hydroxyl radical while the second coordinated nitrite (NO2) is reduced to NO on DNIC coordination sphere to complete the conversion of [PPh3] [Fe(NO)2(ONO)2] into [PPh3][Fe(NO)2Br2]. Under a 4:1 iron porphyrin/DNIC mole ratio, our results demonstrate that [PPN][Fe(NO)2(ONO)2] can serve as a four equivalent nitric oxide donating molecule.
To explore the tendency of nitrite reduction in aqueous phase, we have synthesized water-soluble N-confused porphyrin iron(II) complexes. Tetraphenyl N-confused porphyrin (NCTPP), bearing four 4-sulfonatophenyl groups at the meso positions, and its iron(II) complex, [FeII(HNCPSH)Br], were synthesized. The solution IR studies showed the formation of {Fe(NO)}7 [Fe(HNCPS)NO] as the final product when 0.5 equiv of sodium nitrite was reacted with one equiv of starting [FeII(HNCPSH)Br] in MeOH. We have also confirmed that NaNO2 can directly react with {Fe(NO)}7 and {Fe(NO)}6 iron nitrosyl complexes to result O-atom insertion between Fe-C bond and obtained {Fe(NO)}6 [Fe(CTPPO)NO]. The nitrite reduction reaction in aqueous solution observed the formation of iron nitrosyl complex as in MeOH
|
|---|
