F. Couty, François Durrat, G. Evano
Sep 1, 2006
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0
Influential Citations
31
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Journal
European Journal of Organic Chemistry
Abstract
Series of enantiomerically pure 3-alkenylpyrrolidines, substituted azepanes and stereodefined aminoalkenes were synthesized from 2-alkenylazetidinium trifluoromethanesulfonate salts. The high chemoselectivity of these reactions was found to be strongly dependent both on the nature of the base involved in the process (PhLi or KHMDS) and on the relative cis or trans stereochemistry of the intermediate ammonium ylide. When the ylide and the adjacent alkene are trans, a [1,2] sigmatropic shift occurs exclusively, producing a pyrrolidine with high levels of regioselectivity. On the other hand, clean conversion into 4,5-dehydroazepanes through a [2,3] sigmatropic shift is observed when these two groups are in a cis relationship.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)