Investigation of the Lithiation-Trapping of an N-Boc Bispidine-Ketal: Reactivity and Diastereoselectivity

This paper is dedicated to the memory of Manfred Schlosser for his numerous pioneering contributions to synthetic organometallic chemistry

Abstract

The lithiation-trapping of an N-Boc bispidine-ketal using s-BuLi/TMEDA has been studied. Key findings include an activating effect of the 4-ketal group on the lithiation and complete diastereoselectivity with methylation and Cu-mediated allylation. In contrast, reduced diastereoselectivity was noted for direct allylation and silylation; mechanistic explanations are proposed.

Key words

organolithium reagents - lithiation - stereoselective synthesis - diastereoselectivity - bispidines

• References and Notes

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