Abstract
Crystal Structure of a Tetrahydro-1(1H)-isoindolone.
The structure of the tetrahydro-1(1H)-isoindolone 4a, the product of an intra- molecular Diels-Alder addition, has been determined by X-ray analysis. The revised relative configuration of 4a suggests a formation via the exo-transition state of the [4+2]-cycloaddition, followed by enolization to the more stable cis-fused product.