64108-15-2Relevant academic research and scientific papers
Experimental and theoretical studies on the bismuth-triflate-catalysed cycloisomerisation of 1,6,10-trienes and aryl polyenes
Godeau, Julien,Fontaine-Vive, Fabien,Antoniotti, Sylvain,Du?ach, Elisabet
supporting information, p. 16815 - 16822 (2013/03/28)
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/Br?nsted acid catalyst with water molecules is proposed, supported by experimental and theoretical data. Round and round: Cycloisomerisation reaction mechanisms involving polyenes and aryl trienes catalysed by bismuth triflate were studied experimentally and theoretically. The diastereoselectivity observed during the reaction of E or Z olefins in favour of trans-fused bicyclic products is discussed. The nature of the active catalytic species derived from bismuth triflate was also investigated, and formation of a hybrid Lewis acid/Br?nsted acid catalyst with water molecules is proposed (see figure). Copyright
