Diels-Alder adducts of medium-ring carbocyclic dienes prepared by rearrangement of catalytically generated cyclic oxonium ylides

C Wilson; J S Clark; A L Bate; A J Blake; T Grinter; S J Teat

doi:10.1107/s0108270101013440

Diels-Alder adducts of medium-ring carbocyclic dienes prepared by rearrangement of catalytically generated cyclic oxonium ylides

Acta Crystallogr C. 2001 Nov;57(Pt 11):1326-9. doi: 10.1107/s0108270101013440. Epub 2001 Nov 13.

Authors

C Wilson¹, J S Clark, A L Bate, A J Blake, T Grinter, S J Teat

Affiliation

¹ School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, England. claire.wilson@nott.ac.uk

PMID: 11706264
DOI: 10.1107/s0108270101013440

Abstract

The novel bicyclic and tricyclic systems dimethyl (4aS*,6S*)-6-methoxy-7-oxo-4a,5,6,7,8,9-hexahydro-2H-benzocycloheptene-3,4-dicarboxylate, C(16)H(20)O(6), (I), dimethyl (4aS*,6R*)-6-methoxy-7-oxo-4a,5,6,7,8,9-hexahydro-2H-benzocycloheptene-3,4-dicarboxylate, C(16)H(20)O(6), (II), (3aS*,9R*,10aS*,10bR*)-9-methoxy-2-oxa-1,3a,4,6,7,8,9,10,10a,10b-decahydro-3H-cyclohepta[e]indene-1,3,8-trione, C(14)H(16)O(5), (III), and (1S*,2R*,9S*,10aR*)-9-methoxy-8-oxo-1,2,3,5,6,7,8,9,10,10a-decahydrobenzocyclooctene-1,2-dicarboxylic acid, C(15)H(20)O(6), (IV), have been crystallographically characterized, allowing the determination of the relative configuration of the stereogenic centres. The poor quality of the dicarboxylic acid crystals necessitated the use of synchrotron radiation.