Prolinethioamides versus Prolinamides in Organocatalyzed Aldol Reactions - A Comparative Study
نویسندگان
چکیده
Various organocatalysts have been developed for the aldol reaction but particular attention has been paid to prolinamide derivatives. They are easy to prepare and their catalytic activity can be readily tuned through structural modification. In this review, the comparison of catalytic activities between prolinethioamides and their respective amides in direct asymmetric aldol reactions is presented.
منابع مشابه
Enantioselective direct aldol reactions catalyzed by L-prolinamide derivatives.
l-Prolinamides 2, prepared from l-proline and simple aliphatic and aromatic amines, have been found to be active catalysts for the direct aldol reaction of 4-nitrobenzaldehyde with neat acetone at room temperature. They give moderate enantioselectivities of up to 46% enantiomeric excess (ee). The enantioselectivity increases as the amide N-H becomes a better hydrogen bond donor. l-Prolinamides ...
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عنوان ژورنال:
- Symmetry
دوره 3 شماره
صفحات -
تاریخ انتشار 2011