Asymmetric Synthesis of -Substituted
Aldehydes by Pd-Catalyzed Asymmetric
Allylic Alkylation-Alkene
Isomerization-Claisen Rearrangement
Barry M. Trost* andTing Zhang
Department of Chemistry, Stanford University, Stanford, California 94305-5080
bmtrost@stanford.edu
Received October 9, 2006
Abstract:
Enantiospecific aliphatic Claisen rearrangement was realized with generally high chirality transfer. The requisite substrates were synthesized
via Pd-catalyzed asymmetric allylic alkylation (AAA) from easily obtained starting materials. After protection, the resultant bisallyl ethers
underwent olefin isomerization and in situ Claisen rearrangement (ICR) to generate -chiral aldehydes. Remarkable chemoselectivity in the
olefin isomerization step was observed. An asymmetric synthesis of communiol A was accomplished applying this methodology.
-Substituted
Aldehydes by Pd-Catalyzed Asymmetric
Allylic Alkylation-Alkene
Isomerization-Claisen Rearrangement
