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Stereoselectivity in Phenylselenoetherification of (Z)- and (E)-hex-4-en-ols Facilitated by Pyridine and Some Lewis Acids
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1  Department of Chemistry, University of Kragujevac, Radoja Domanovića 12, 34000 Kragujevac, Serbia

Abstract: Studies on the stereoselective phenylselenoetherification of (Z)- and (E)-hex-4-en-ols is described. (Z)-Alkenol is envisage to facilitate the 5-exo favored cyclization, while (E)-izomer facilitate the 6-endo favored cyclization. Diastereomeric ratio of the cyclic products depends on counterion and reaction temperature. We found that external additives, such as pyridine and some Lewis acids coordinating to the electrophilic species are used to control the course of cyclizations with high degrees of efficiency and improve the level of stereoinduction. The course of cyclization can be directed as desired by the choice of the electrophile and the additives used in the reaction.
Keywords: alcohols, cyclic ethers, cyclization, electrophiles, Lewis acids, selenium reagents
Comments on this paper
Claudio Santi
related litterature
Concerning the topics of your communication I suggest to consider also this really close examples:

Tiecco et al. Eur Joc 1999, 797
Landais Tet. Lett 1995, 2987
Landais Synlett 1995, 1191
Kahan JACS 1987, 109
“Organoselenium Chemistry: Modern Developments in Organic Synthesis”: Tiecco, M. Top. Curr. Chem. 2000, pag32 for asymmetric version

geometry dash
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