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Allylation and Crotylation of Ketones and Aldehydes Using Potassium Organotrifluoroborate Salts under Lewis Acid and Montmorillonite K10 Catalyzed Conditions

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Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
†Current address: Department of Chemistry and Biochemistry, University of Windsor, 273-1 Essex Hall, 401 Sunset Ave., Windsor, ON, Canada.
Cite this: Org. Lett. 2009, 11, 12, 2631–2634
Publication Date (Web):May 27, 2009
https://doi.org/10.1021/ol900599q
Copyright © 2009 American Chemical Society

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    Abstract

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    Two convenient highly diastereoselective protocols for the allylation and crotylation of ketones using practical, air- and water-stable potassium allyl and crotyltrifluoroborate salts have been developed. BF3·OEt2 and montmorillonite clay are used as catalysts to promote additions. The montmorillonite-catalyzed method in particular is very robust, providing a straightforward and scalable method for the allylation and crotylation of a range of ketones and aldehydes.

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