title: Experimental and theoretical studies on the bismuth-triflate-catalysed cycloisomerisation of 1,6,10-trienes and aryl polyenes.
abstract: Cycloisomerisation of polyenes such as diethyl geranylprenylmalonate [(E)-1 a], diethyl geranylphenylmalonate [(E)-2 a] and diethyl cinnamylgeranylmalonate [(E,E)-3 a] catalysed by bismuth triflate was studied from experimental and theoretical viewpoints. Several intermediates were isolated and characterised, and calculated transition-state structures are proposed for the three reactions. The diastereoselectivity observed during the reaction of (E)- or (Z)-2 a in favour of the formation of trans-fused bicyclic products is discussed in detail. The nature of the active catalytic species derived from bismuth triflate was also investigated, and the formation of a hybrid Lewis acid/Brønsted acid catalyst with water molecules is proposed, supported by experimental and theoretical data.
authors.affiliation: Institut de Chimie de Nice, UMR, Université de Nice Sophia Antipolis-CNRS, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Godeau
authors.forename: Fabien
authors.initials: F
authors.lastname: Fontaine-Vive
authors.forename: Sylvain
authors.initials: S
authors.lastname: Antoniotti
authors.forename: Elisabet
authors.initials: E
authors.lastname: Duñach
mesh_terms: D001643:Bridged Bicyclo Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D060326:Chemistry Techniques, Synthetic; D058116:Lewis Acids / Q000737:chemistry; D008314:Malonates / Q000737:chemistry*; D008698:Mesylates / Q000737:chemistry*; D008956:Models, Chemical; D015394:Molecular Structure; D011090:Polyenes / Q000737:chemistry*; D013237:Stereoisomerism; D013729:Terpenes / Q000737:chemistry*
chemical_list: D001643:Bridged Bicyclo Compounds; D058116:Lewis Acids; D008314:Malonates; D008698:Mesylates; D011090:Polyenes; D013729:Terpenes; C445789:Bi(OTf)3