Enantioselective Total Synthesis of Cannogenol-3-O-α-l-rhamnoside via Sequential Cu(II)-Catalyzed Michael Addition/Intramolecular Aldol Cyclization Reactions
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چکیده
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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ژورنال
عنوان ژورنال: Organic Letters
سال: 2017
ISSN: 1523-7060,1523-7052
DOI: 10.1021/acs.orglett.7b03513