Highly enantioselective cascade synthesis of spiropyrazolones.
نویسندگان
چکیده
An efficient synthesis of spiropyrazolones based on organocatalysis is described. The reaction between pyrazolones, enolizable aldehydes and enals is catalyzed by secondary amine catalysts and affords the final spiro compounds bearing four contiguous chiral centers in good yields and excellent diastereo- and enantioselectivities.
منابع مشابه
Highly diastereoselective synthesis of spiropyrazolones.
We report a highly diastereoselective synthesis of spiropyrazolones catalyzed by secondary amines. The reported Michael-Aldol cascade reaction affords the desired spiropyrazolones bearing four chiral centers as a single diastereomer in excellent yields.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 9 19 شماره
صفحات -
تاریخ انتشار 2011