The role of an aromatic group in remote chiral induction during conjugate addition of α-sulfonylallylic carbanions to ethyl crotonate
نویسندگان
چکیده
The impact of a remote aromatic nucleus on the stereochemical outcome of the conjugate addition of alpha-sulfonylallylic carbanions to an alpha,beta-unsaturated ester was investigated. alpha-Regioselectivity coupled with anti-diastereoselectivity is accompanied by a prominent preference for relative configuration 3 over 4. The 9-anthryl moiety has shown itself greatly superior over all other groups in this bias. A lithium ion-aromatic pi interaction has been postulated as decisive for the remote transmission of chirality.
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عنوان ژورنال:
- Beilstein Journal of Organic Chemistry
دوره 4 شماره
صفحات -
تاریخ انتشار 2008