Synlett 2015; 26(17): 2381-2384
DOI: 10.1055/s-0034-1378817
cluster
© Georg Thieme Verlag Stuttgart · New York

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

Darren Stead
a  Department of Chemistry, University of York, Heslington, York YO10 5DD, UK   Email: peter.obrien@york.ac.uk
,
Peter O’Brien*
a  Department of Chemistry, University of York, Heslington, York YO10 5DD, UK   Email: peter.obrien@york.ac.uk
,
Adam Sanderson
b  Eli Lilly and Co. Ltd, Lilly Research Centre, Erl Wood Manor, Sunninghill Rd, Windlesham, Surrey, GU20 6PH, UK
› Author Affiliations
Further Information

Publication History

Received: 27 April 2015

Accepted after revision: 08 July 2015

Publication Date:
11 August 2015 (online)


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.

Supporting Information

 
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