The diastereoselective synthesis of functionalised spirocyclic lactams and lactones using a Cope elimination/intramolecular nitrone cycloaddition strategy
摘要:
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.
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.
The synthesis of functionalised chiral bicyclic lactam and lactone N-oxides using a tandem Cope elimination/reverse Cope elimination protocol
作者:Gemma L. Ellis、Ian A. O’Neil、V. Elena Ramos、Ed Cleator、S. Barret Kalindjian、Alan P. Chorlton、David J. Tapolczay
DOI:10.1016/j.tetlet.2007.01.045
日期:2007.3
derivatives of (S)-proline and (R)-pipecolic acid have been prepared using a Copeelimination. These undergo reverse Copeelimination onto a pendant double bond to give bicyclic lactam and lactone N-oxides containing three contiguous chiral centres, this extends the scope and applicability of the reverse Copeelimination in the synthesis of heterocyclic systems by incorporation of the lactone and lactam