Liebigs Annalen der Chemie

Chiral Organometallic Reagents, VI. Diastereomeric α??Phenylseleno Alkyllithium Compounds, Generation and Reactions

RW Hoffmann, M Bewersdorf

Index: Hoffmann, Reinhard W.; Bewersdorf, Martin Liebigs Annalen der Chemie, 1992 , # 6 p. 643 - 654

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Citation Number: 7

Abstract

Abstract The selenoacetals 4 having a chiral center in the β-position were subjected to selenium/lithium exchange by butyllithium in ether. The resulting α-phenylseleno alkyllithium compounds 5 undergo rapid epimerization at− 78 C. Trapping of these organolithium compounds by ketones or aldehydes appears to be faster than the epimerization. The ratio of the trapping products therefore reflects the equilibrium ratio of the diastereomeric α- ...