Intramolecular Diels−Alder Reactions of Ester-Tethered 1,7,9-Decatrienoates: Bis[chloro(methyl)aluminum]trifluoromethanesulfonamide as a Catalyst
摘要:
The intramolecular Diels-Alder reaction of 1,7,9-decatrienoate derivative with an ester tether is efficiently catalyzed by the bidentate Lewis acid,/bis-aluminated trifluoromethanesulfonamide.
(E)- and (Z)-1-(Phenylsulfonyl)-4-(trimethylsilyl)-2-butenes: Synthetic Equivalents for the 1-(1,3-Butadienyl) Anion and the 1,1-(1,3-Butadienyl) Dianion
Intramolecular Diels–Alder (IMDA) reaction of α-fluoroacrylate derivatives 1a–e having 1,7,9-decatrienoate system is efficiently promoted by the novelbidentateLewisacid A generated in situ by mixing 3,3′,5,5′-tetrabromo-1,1′-biphenyl-2,2′-diol (Br4BIPOL, 1 mol) and trimethylaluminum (2 mol). The IMDA reaction of α-fluoroacrylates proceeds via endo-boat transition state as in the case of the corresponding