Auxiliary-reagent mediated asymmetric induction in the aza-Claisen rearrangement

✍ Scribed by Mark J. Kurth; Owen H.W. Decker

• Publisher: Elsevier Science
• Year: 1983
• Tongue: French
• Weight: 235 KB
• Volume: 24
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)85948-1

✦ Synopsis

Cbiral induction (?2-74% diastervomeric excess) in an auxiliary-reagent mediated aza-Claisen rearrangement yielding 2-and 3-m&hyZpent-&en&c acids has been demonstrated. Claisen rearrangements ([3,3] sigmatropic reorganization of ally1 vinyl hetero-systems) have been employed in numerous aspects of organic synthesis over the past 15 years.' The foundation for this utility lies in the stereo-differentiating ability of these concerted rearrangements. Application of this intrinsic selectivity to asymmetric induction via chirality transfer, termed "self-inanolative" asymmetric induction,' has been demonstrated in several elegant synthetic studies. Representative examples include the Stork-Raucher3 synthesis of (+)-15(S)-PGA2 from L-erythrose via the normal Claisen rearrangement and the