Organocatalytic asymmetric formal [3+3] cycloaddition reactions of α,β-unsaturated aldehydes with nazarov reagents

Abstract

An organocatalytic asymmetric formal [3+3] cycloaddition reaction of α,β-unsaturated aldehydes with Nazarov reagents promoted by prolinol derivatives afforded, after oxidation, 3,4-dihydropyranones in good yields with high enantioselectivities of up to 97% ee. © 2008 Wiley-VCH Verlag GmbH & Co. KGaA.