The diastereoselective synthesis of functionalised spirocyclic lactams and lactones using a Cope elimination/intramolecular nitrone cycloaddition strategy
作者:Gemma L. Ellis、Ian A. O’Neil、V. Elena Ramos、S. Barret Kalindjian、Alan P. Chorlton、David J. Tapolczay
DOI:10.1016/j.tetlet.2007.01.046
日期:2007.3
Functionalised hydroxylamine derivatives of (S)-proline and pipecolic acid have been prepared using a Cope elimination. These hydroxylamines have been found to undergo oxidation to the nitrone either in the presence of air or a catalytic quantity of TPAP. An intramolecular 1,3-dipolar cycloaddition then occurs between the nitrone and pendant double bond to give tricyclic lactams and lactones with high diastereoselectivity. (c) 2007 Published by Elsevier Ltd.