Free-radical oxidation of para-substituted phenols by hypervalent tert-butylperoxyiodane and tert-butyl hydroperoxide: Synthesis of 4-(tert-butylperoxy)-2,5-cyclohexadien-1-ones
作者:Masahito Ochiai、Akinobu Nakanishi、Akiko Yamada
DOI:10.1016/s0040-4039(97)00781-8
日期:1997.6
Oxidation of 4-alkylphenols 1 by 1-(tert-butylperoxy)-1,2-benziodoxol-3(1H)-one (2) in the presence of tert-butyl hydroperoxide affords selectively 4-(tert-butylperoxy)-2,5-cyclohexadien-1-ones 3 in good yields. Evidence for the involvement of free-radicals is reported.
Synthesis of 2-substituted quinones, vitamin K3, and vitamin K1 from p-cresol. BF3·OEt2-catalyzed methyl migration of 4-tert-butyldioxycyclohexadienones
oxidation of p-cresol with tert-butyl hydroperoxide, in hexafluoro-2-propanol/toluene gave toluquinone efficiently. The reaction can be applied to the regio-selective short-step syntheses of vitamin K3 and vitaminK1 from p-cresol.
Dirhodium-Catalyzed Phenol and Aniline Oxidations with T-HYDRO. Substrate Scope and Mechanism of Oxidation
作者:Maxim O. Ratnikov、Linda E. Farkas、Emily C. McLaughlin、Grace Chiou、Hojae Choi、Sahar H. El-Khalafy、Michael P. Doyle
DOI:10.1021/jo1024865
日期:2011.4.15
and CuI are provided, and mechanistic comparisons are made between these catalysts that are based on diastereoselectivity (reactions with estrone), regioselectivity (reactions with p-tert-butylphenol), and chemoselectivity in the formation of 4-(tert-butyldioxy)cyclohexadienones. The data obtained are consistent with hydrogen atom abstraction by the tert-butylperoxy radical followed by radical combination