Concerning the reactivity of dioxiranes. Observations from experiments and theory

被引：27

作者：

Annese, Cosimo ^{[2
]}

D'Accolti, Lucia ^{[2
]}

Dinoi, Anna ^{[2
]}

Fusco, Caterina ^{[3
]}

Gandolfi, Remo ^{[1
]}

Curci, Ruggero ^{[2
]}

机构：

[1] Univ Pavia, Dipartimento Chim Organ, I-27100 Pavia, Italy

[2] Univ Bari, Dipartmento Chim, I-70126 Bari, Italy

[3] ICCOM, CNR, I-70126 Bari, Italy

来源：

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY | 2008年 / 130卷 / 04期

关键词：

D O I：

10.1021/ja075068u

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The challenging hypothesis of a "biphilic" (i.e., electrophilic vs nucleophilic) character for dioxirane reactivity, which envisages that electron-poor alkenes are attacked by dioxiranes in a nucleophilic fashion, could not be sustained experimentally. Rate data, which estimate Hammett "rho" values for the epoxidation of 3- or 4-substituted cinnamonitriles X center dot Ph-CH=CH-CN, unequivocally allow one to establish that dioxiranes epoxidize electrophilically even alkenes carrying electron-withdrawing groups. The greater propensity of methyl(trifluoromethyl)dioxirane TFDO (1b) to act as an electrophilic oxidant with respect to dimethyldioxirane DDO (1a) parallels the cathode reduction potentials for the two dioxiranes, as measured by Cyclic voltammetry. A simple FMO approach for alkene epoxidation is helpful to conceive a likely rationale for the greater oxidizing power of TFDO as compared to DDO.

引用

页码：1197 / 1204

页数：8

共 77 条

[1] Remarks on official methods employing boron trifluoride in the preparation of methyl esters of the fatty acids of fish oils [J].