Dihydrooxazine oxides as key intermediates in organocatalytic Michael additions of aldehydes to nitroalkenes.
نویسندگان
چکیده
Pause and play: dihydrooxazine oxides are stable intermediates that are protonated directly, without the intermediacy of the zwitterions, in organocatalytic Michael additions of aldehydes and nitroalkenes (see scheme, R=alkyl). Protonation of these species explains both the role of the acid co-catalyst in these reactions, and the observed stereochemistry when the reaction is conducted with α-alkylnitroalkenes.
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ورودعنوان ژورنال:
- Angewandte Chemie
دوره 51 52 شماره
صفحات -
تاریخ انتشار 2012