Asymmetric synthesis of cyclopropanes and dihydrofurans based on phosphine oxide chemistry.
نویسندگان
چکیده
The asymmetric synthesis of gamma-azido trans-cyclopropyl ketones is accomplished via a short, simple and efficient sequence. The cyclopropanation step is achieved by an intramolecular nucleophilic ring closure, with a diphenylphosphinate leaving group, to give trans-cyclopropane exclusively. beta-Keto-diphenylphosphine oxides cyclise to form optically active dihydrofurans. All possible diastereoisomers of dihydrofurans can be prepared selectively starting from the same olefin.
منابع مشابه
Asymmetric synthesis of trans-disubstituted cyclopropanes using phosphine oxides and phosphine boranes.
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عنوان ژورنال:
- Organic & biomolecular chemistry
دوره 4 16 شماره
صفحات -
تاریخ انتشار 2006