Magnesium halide-catalyzed anti-aldol reactions of chiral N-acylthiazolidinethiones.
نویسندگان
چکیده
[reaction: see text] Diastereoselective direct aldol reactions of chiral N-acylthiazolidinethiones occur in high yield with preference for the illustrated anti diastereomer. This reaction is catalyzed by 10% MgBr2.OEt2 in the presence of triethylamine and chlorotrimethylsilane. Yields range from 56 to 93% with diastereoselectivity up to 19:1 for a variety of N-acylthiazolidinethiones and unsaturated aldehydes.
منابع مشابه
Diastereoselective magnesium halide-catalyzed anti-aldol reactions of chiral N-acyloxazolidinones.
A chiral auxilliary-based direct aldol reaction is reported. The reactions are catalytic in magnesium salts and are facilitated by silylation with chlorotrimethylsilane. The adducts isolated are in high diastereoselectivity (up to 32:1 dr) and favor the anti-aldol diastereomer B. Reactions are operationally simple and can be run under ambient atmosphere without rigorous exclusion of water. Many...
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عنوان ژورنال:
- Organic letters
دوره 4 7 شماره
صفحات -
تاریخ انتشار 2002