Salen Promoted Enantioselective Nazarov Cyclizations of Activated and Unactivated Dienones
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چکیده
منابع مشابه
Salen Promoted Enantioselective Nazarov Cyclizations of Activated and Unactivated Dienones
A novel class of chiral 5,5'-di(2,4,6-trialkyl)aryl salen-metal complexes have been developed and shown to catalyze highly enantioselective Nazarov cyclization reactions, giving rise to cyclopentenoids in 90:10-98:2 er. Significantly, the catalysts also promote, for the first time, highly enantioselective Nazarov reactions of "unactivated" dienones, producing hydrindenone products having in pla...
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The Nazarov cyclization of divinyl ketones gives access to cyclopentenones. Replacing one of the vinyl groups by a cyclopropane leads to a formal homo-Nazarov process for the synthesis of cyclohexenones. In contrast to the Nazarov reaction, the cyclization of vinyl-cyclopropyl ketones is a stepwise process, often requiring harsh conditions. Herein, we describe two different approaches for furth...
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ژورنال
عنوان ژورنال: Journal of the American Chemical Society
سال: 2013
ISSN: 0002-7863,1520-5126
DOI: 10.1021/ja401908m