Double axial chirality promoted asymmetric [2,3] Stevens rearrangement of N-cinnamyl L-alanine amide-derived ammonium ylides.
نویسندگان
چکیده
The base-induced asymmetric [2,3] Stevens rearrangement of N-cinnamyl tetraalkylammonium ylides derived from L-alanine amides proceeds via a double axially chiral intermediate to afford the corresponding α-substituted alanine derivatives with high enantio- and diastereoselectivities.
منابع مشابه
Asymmetric Sommelet-Hauser rearrangement of N-benzylic ammonium salts.
The Stevens and Sommelet–Hauser rearrangement of ammonium ylides are known as useful transformations for organic synthesis because they convert a readily accessible C–N bond into a new C–C bond. The Stevens rearrangement has been widely used for the asymmetric synthesis of α-amino acid derivatives, whereas the Sommelet–Hauser rearrangement is much less common because the Sommelet–Hauser rearran...
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Benzotetramisole promotes the catalytic asymmetric [2,3]-rearrangement of allylic quaternary ammonium salts (either isolated or prepared in situ from p-nitrophenyl bromoacetate and the corresponding allylic amine), generating syn-α-amino acid derivatives with excellent diastereo- and enantioselectivity (up to >95:5 dr; up to >99% ee).
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عنوان ژورنال:
- Chemical communications
دوره 50 52 شماره
صفحات -
تاریخ انتشار 2014