新しい大環状ポリアミン-Ni (II) 錯体による分子状酸素の捕捉と活性化

生体機能に類似した可逆的酸素捕捉反応と芳香環の水酸化

抄録

Substituted and unsubstituted dioxo [16] aneN₅ (1, 4, 7, 10, 13-pentaazacyclohexadecane-14, 16- dione) form stable 1 : 1 square pyramidal complexes with Ni (II), which posess two deprotonated amide donors in equatorial positions. The high spin Ni (II) complexes show very low Ni^{II, III} redox potentials +0.24V vs. SCE and react with molecular oxygen to from 1 : 1 Ni (III) -O^-₂ adducts in aqueous solution. The oxygen adducts hydroxylate electron- rich aromatic compounds to form phenol derivatives. This is a good model reaction of biological aromatic hydroxylation since the oxygen atom incorporated into aromatic rings is entirely from molecular oxygen.