Nucleophilic additions of chiral non-racemic enolates to N-benzyl-C-(alkoxymethyl) nitrones
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چکیده
منابع مشابه
Efficient stereoselective nucleophilic addition of pyrroles to chiral nitrones.
Regioselective additions of pyrroles to a variety of optically active nitrones under smooth acidic conditions lead to chiral pyrrolic N-hydroxylamines in good to excellent yields. Depending on the position of the chirality on the nitrone partner, the addition products have been isolated with high diastereoselectivity levels. Reaction of glyoxylate based chiral nitrones either at the C-2 or at t...
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Asymmetric α-2-tosylethenylation of (S)-2-(pyrrolidin-1-yl)propanoic acid esters was shown to produce good yields with high enantioselectivities. The reaction proceeds via the formation of a non-racemic ammonium enolate without an external source of chirality.
متن کاملTitanium enolates of thiazolidinethione chiral auxiliaries: versatile tools for asymmetric aldol additions.
[formula: see text] Asymmetric aldol additions using chlorotitanium enolates of thiazolidinethione propionates proceed with high diastereoselectivity for the "Evans" or "non-Evans" syn product depending on the nature and amount of the base used. With (-)-sparteine as the base, selectivities of 97:3 to > 99:1 were obtained for the Evans syn products with 2 equivalents of base and for the non-Eva...
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ژورنال
عنوان ژورنال: Arkivoc
سال: 2003
ISSN: 1551-7012
DOI: 10.3998/ark.5550190.0005.407