Dedicated to Prof. Th. J. de Boer on the occasion of his retirement from the chair of Organic Chemistry at the University of Amsterdam.
Reactions of enamines of cyclodecanone and cyclododecanone with dimethyl acetylenedicarboxylate in apolar and in polar solvents†
Article first published online: 2 SEP 2010
Copyright © 1986 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Recueil des Travaux Chimiques des Pays-Bas
Volume 105, Issue 10, pages 380–386, 1986
How to Cite
Vos, G. J. M., Benders, P. H., Egberink, R. J. M., Reinhoudt, D. N., Harkema, S., van Hummel, G. J. and van der Weerdt, A. J. A. (1986), Reactions of enamines of cyclodecanone and cyclododecanone with dimethyl acetylenedicarboxylate in apolar and in polar solvents. Recl. Trav. Chim. Pays-Bas, 105: 380–386. doi: 10.1002/recl.19861051011
- Issue published online: 2 SEP 2010
- Article first published online: 2 SEP 2010
- Manuscript Received: 4 MAR 1986
- The Netherlands Foundation
- Future Technical ScienceBranch/Division of the Netherlands Organization
Enamines of cyclodecanone and cyclododecanone (1a-d) react with dimethyl acetylenedicarboxylate (DMAD) in an apolar solvent via (2 + 2) cycloaddition and conrotatory opening of the cyclobutene ring in 3 to give the cis,trans-cycloalkadienes 5a-d in yields of 44–85%. The compounds 5 do not undergo further thermal or photochemical transformation of the cis,trans moiety. In methanol, the enamines react with DMAD to give bicyclo[7.2.1]dodecene (8a) or bicyclo[9.2.1]tetradecene (8b and 8c) derivatives. These reactions take place via intramolecular nucleophilic addition of the enamine moiety to the α-methoxycarbonyl group in 10, which is formed from the intermediate Michael adduct 9. The structure of 8b was determined by single-crystal X-ray analysis.