Further unexpected boron trifluoride-catalyzed reactions of taxoids with α- and β-4,20-epoxides
Abstract
Three unusual taxinine derivatives, the cyclobutane 3, the dioxane 4, and the orthoester 5, were obtained by boron trifluoride-catalyzed reactions of β- and α-4,20-epoxy-5-O-triethylsilyltaxinine A (1 and 2, respectively) (3 and 4 from 1; 5 from 2).