Control of the mode selectivity (ene reaction versus [2 + 2] cycloaddition) in the photooxygenation of ene carbamates: directing effect of an alkenylic nitrogen functionality.
نویسندگان
چکیده
The geometry of the double bond in oxazolidinone-substituted ene carbamates controls the mode selectivity (ene reaction versus [2+2] cycloaddition) of singlet oxygen through stereoelectronic effects, whereas the chiral auxiliary provides high diastereoselectivity through steric shielding.
منابع مشابه
Enecarbamates as selective substrates in oxidations: chiral-auxiliary-controlled mode selectivity and diastereoselectivity in the [2+2] cycloaddition and ene reaction of singlet oxygen and in the epoxidation by DMD and mCPBA.
The stereochemical course of the oxidation of chiral oxazolidinone-substituted enecarbamates has been studied for singlet oxygen ((1)O(2)), dimethyldioxirane (DMD), and m-chloroperbenzoic acid (mCPBA) by examining of the special structural and stereoelectronic features of the enecarbamates. Valuable mechanistic insight into these selective oxidations is gained. Whereas the R(1) substituent on t...
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ورودعنوان ژورنال:
- Journal of the American Chemical Society
دوره 124 47 شماره
صفحات -
تاریخ انتشار 2002