Electron Transfer Chemistry of Organometallic Porphyrins

有机金属卟啉的电子转移化学

• 批准号: 08044083
• 负责人: FUKUZUMI Shunichi
• 金额: $ 4.48万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for international Scientific Research
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08044083/
• 关键词: Organometallics; Porphyrin; Electron Transfer; Redox Potential; Migration Reaction; Oxidation; ESR; Axial Ligand Coordination; 有機金属ポルフィリン; 電子移動; 転移; EPR; 速度論

The one-electron oxidation of alkyl and aryl metal sigma-bonded porphyrins is often followed by a metal to nitrogen migration of the sigma-bonded organic ligand. Several studies of oxidized cobalt sigma-bonded porphyrins have suggested that a Co^<III> pi cation radical rather than a Co^<IV> cation is generated prior to the migration.The present study combines the use of electrochemistry, UV-vis and ESR spectroscopy and stopped flow kinetics to investigate the reactions and properties of singly oxidized organoporphyrins of the type (P) M (R) and (P) M (R)(L) where P = the dianion of substituted porphyrins : TPP or OEP,M = Co or Fe, R = n-Bu, Et, Me or Ph, L = acetonitrile or a substituted pyridine. The results of our studies show clearly that a (TPP) Co^<IV> (R) complex can be generated under specific solution conditions and the cleavage of the cobalt-carbon bond occurs via a rate-determining intramolecular electron transfer from R to Co and this results in a metal to nitrogen migration of the R group. In a similar mannar, one-electron oxidation of an aryl sigma-bonded iron porphyrin, (OEP) Fe^<III> (R) results in the formation of an Fe^<IV> center which is invariably generated prior to migration.

烷基和芳基金属sigma键卟啉的单电子氧化通常伴随着sigma键有机配体的金属向氮迁移。对氧化钴sigma键卟啉的一些研究表明，在迁移之前会产生Co^<III>阳离子自由基，而不是Co^<IV>阳离子。本研究结合了电化学、紫外可见光谱和ESR光谱以及停止流动动力学的使用，研究了(P) M (R)和(P) M (R)(L)型单氧化有机卟啉的反应和性质，其中P =取代卟啉的离子：TPP或OEP，M = Co或Fe， R = n-Bu, Et， Me或Ph， L =乙腈或取代吡啶。我们的研究结果清楚地表明，（TPP） Co^<IV> (R)配合物可以在特定的溶液条件下生成，并且通过从R到Co的速率决定的分子内电子转移发生钴碳键的裂解，这导致R基团的金属向氮迁移。以类似的方式，芳基sigma键铁卟啉（OEP） Fe^<III> (R)的单电子氧化导致Fe^<IV>中心的形成，该中心总是在迁移之前生成。

项目成果

Shunichi Fukuzumi et al.: "Kinetic and Thermodynamic Studies of Iron (III) and Iron (IV) Sigma Bonded Porphyrins.Formation and Reactivity of [(OEP) Fe (R)]^<n+>where OEP is the Dianion of Octaethlporphyrin,n=0,1,2,3and R=C_6H_5,3,4,5-C_6F_3H_2,2,4,6-C_6F_

Shunichi Fukuzumi 等人：“铁 (III) 和铁 (IV) Sigma 键合卟啉的动力学和热力学研究。[(OEP) Fe (R)]^<n > 的形成和反应性，其中 OEP 是八乙基卟啉的二价阴离子，

Shunichi Fukuzumi et al.: "Kinetic and Thermodynamic Studies of Iron (III) and Iron (IV) Sigma Bonded Porphyrins. Formation and Reactivity of [(OEP)Fe(R)]^<n+> where OEP is the Dianion of Octaethylporphyrin, n = 0, l, 2,3 and R = C_6H_5,3,4,5-C_6F_3H_2,2,

Shunichi Fukuzumi 等人：“铁 (III) 和铁 (IV) Sigma 键合卟啉的动力学和热力学研究。[(OEP)Fe(R)]^<n > 的形成和反应性，其中 OEP 是八乙基卟啉的二价阴离子，

Shunichi Fukuzumi: "Catalysis on Electron Transfer and the Mechanistic Insight into Redox Reactions" Bull.Chem.Soc.Jpn.70. 1-28 (1997)

Shunichi Fukuzumi：“电子转移催化和氧化还原反应的机理洞察”Bull.Chem.Soc.Jpn.70。

Shunichi Fukuzumi et al.: "Kinetic and Thermodynamic Studies of Iron(III)and Iron(IV)Sigma Bonded Porphyrins.Formation and Reactivity of [(OEP)Fe(R)]^<n+> where OEP is the Dianion of Octaethylporphyrin,n=0,1,2,3 and R=C_6H_5,3,4,5-C_6F_3H_2,2,4,6-C_6F_3H_

Shunichi Fukuzumi 等人：“铁(III)和铁(IV)Sigma键合卟啉的动力学和热力学研究。[(OEP)Fe(R)]^<n>的形成和反应性，其中OEP是八乙基卟啉的二价阴离子，

Shunichi Fukuzumi et al.: "Direct Observation of Radical Intermediates Derived from Thiamin Coenzyme Models and the Redox Behavior" Angew. Chem. Int. Ed.37・(印刷中). (1998)

Shunichi Fukuzumi 等：“从硫胺素辅酶模型衍生的自由基中间体和氧化还原行为”Angew Chem.Ed.37（出版中）。