Lewis Acid Induced Switch of Torquoselectivity in the Nazarov Cyclization of Activated Dienones Bearing a Chiral Sulfoxide

Erwann Grenet; Jean Martínez; Xavier J Salom-Roig

doi:10.1002/chem.201603920

Lewis Acid Induced Switch of Torquoselectivity in the Nazarov Cyclization of Activated Dienones Bearing a Chiral Sulfoxide

Chemistry. 2016 Nov 14;22(47):16770-16773. doi: 10.1002/chem.201603920. Epub 2016 Oct 13.

Authors

Erwann Grenet¹, Jean Martínez¹, Xavier J Salom-Roig¹

Affiliation

¹ Institut de Biomolécules Max Mousseron (IBMM), UMR 5247, Université de Montpellier, CNRS, ENSCM, Place Eugène Bataillon, 34095, Montpellier, France.

PMID: 27618730
DOI: 10.1002/chem.201603920

Abstract

A Nazarov cyclization of activated dienones bearing a dihydropyran as an electron-donating group (EDG) and a chiral sulfoxide group as an electron-withdrawing group (EWG) and chiral inductor is described. The direction of the torquoselectivity depends highly on the nature of the Lewis acid promoter. This diastereodivergent strategy furnishes both trans stereoisomers from a common precursor. The potential of the Nazarov cyclization products was highlighted by further synthetic elaboration.

Keywords: Lewis acids; Nazarov reaction; chiral sulfoxides; electrocyclic reactions; torquoselectivity.