Enantioselective Diels-Alder reaction of o-quinodimethanes by utilizing tartaric acid ester as a chiral auxiliary

The asymmetric Diels-Alder reaction of o-quinodimethanes, generated from benzocyclobutenols in situ, with fumaric acid esters was achieved by utilizing diisopropyl (R,R)-tartrate as a chiral auxiliary to afford the corresponding optically active 1,2-cis-substituted 1-hydroxy tetrahydronaphthalene derivatives with enantioselectivities up to 83% ee. (c) 2006 Elsevier Ltd. All rights reserved.