Lewis Acid Induced Switch of Torquoselectivity in the Nazarov Cyclization of Activated Dienones Bearing a Chiral Sulfoxide.
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.
Institut de Biomolécules Max Mousseron (IBMM), UMR 5247, Université de Montpellier, CNRS, ENSCM, Place Eugène Bataillon, 34095, Montpellier, France.
Erwann
http://orcid.org/0000-0002-5249-8766
E
Grenet
Institut de Biomolécules Max Mousseron (IBMM), UMR 5247, Université de Montpellier, CNRS, ENSCM, Place Eugène Bataillon, 34095, Montpellier, France.
Jean
http://orcid.org/0000-0002-9267-4621
J
Martínez
Institut de Biomolécules Max Mousseron (IBMM), UMR 5247, Université de Montpellier, CNRS, ENSCM, Place Eugène Bataillon, 34095, Montpellier, France.
Xavier J
http://orcid.org/0000-0002-5638-4475
XJ
Salom-Roig
Lewis acids; Nazarov reaction; chiral sulfoxides; electrocyclic reactions; torquoselectivity