Time-Resolved Kinetic Study of the Electron-Transfer Reactions between Ring-Substituted Cumyloxyl Radicals and Alkylferrocenes. Evidence for an Inner-Sphere Mechanism

被引：8

作者：

Bietti, Massimo ^{[1
]}

DiLabio, Gino A. ^{[2
]}

Lanzalunga, Osvaldo ^{[3
]}

Salamone, Michela ^{[1
]}

机构：

[1] Univ Tor Vergata, Dipartimento Sci & Tecnol Chim, I-00133 Rome, Italy

[2] Natl Res Council Canada, Natl Inst Nanotechnol, Edmonton, AB T6G 2M9, Canada

[3] Univ Roma La Sapienza, Dipartimento Chim, Ist CNR Metodol Chim IMC CNR, Sez Meccanisrni Reaz, I-00185 Rome, Italy

来源：

JOURNAL OF ORGANIC CHEMISTRY | 2011年 / 76卷 / 06期

关键词：

DENSITY-FUNCTIONAL THEORY; ABSORPTION-SPECTRA; OUTER-SPHERE; REDUCTION; POTENTIALS; ALKYL; THERMOCHEMISTRY; ABSTRACTION; BENZYLOXYL; REACTIVITY;

D O I：

10.1021/jo102420p

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

A time-resolved kinetic study of the reactions of ring-substituted cumyloxyl radicals (4-X-CumO(center dot): X = OMe, t-Bu, Me, Cl, CF3) with methylferrocenes (Me(n)Fc: n = 2, 8, 10) has been carried out in acetonitrile solution. Evidence for an electron transfer (ET) process has been obtained for all radicals and an increase in reactivity has been observed on decreasing the oxidation potential of the ferrocene donor and on going from electron-releasing to electron-withdrawing ring substituents. Computations predict the formation of strongly bound pi-stacked 4-X-CumO(center dot)/DcMFc complexes, characterized by intracomplex pi-pi distances around 4 angstrom. These findings point toward a (nonbonded) inner-sphere ET mechanism for the reactions of the 4-X-CumO(center dot)/Me(n)Fc couples.

引用

页码：1789 / 1794

页数：6

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