Cycloaddition reactions of alkyl azides with epoxyenones
1,3-Dipolar cycloaddition reactions of 3-aryl-1-(2-methyloxyranyl)prop-2-en-1-one with benzyl- and butyl azides have been investigated. It is established that this interaction under heating results regioselectively to unstable epoxyalkanoyltriazoline which transform into the mixture consisting of ( Z )-3-aryl-3-(benzylamino)-1-(2-methyloxiran-2-yl)prop-2-en-1-ones, (5-aryl-1-benzyl(butyl)-1 H -1,2,3-triazol-4-yl)(2-methyloxiran-2-yl)methanones and 1-(5-aryl-1-benzyl(butyl)-1 H -1,2,3-triazol-4-yl)-3-hydroxy-2-methylpropan-1-ones. The mechanism of the thermal rearrangement of epoxyalkanoyltriazoline to enaminoketones and epoxy- and b-hydroxyalkanoyltriazoles is investigated and discussed.