Fluorous Dienophiles Are Powerful Diene Scavengers in Diels−Alder Reactions

Abstract
Three fluorous dienophiles have been synthesized, and their value in scavenging an excess diene after Diels−Alder reactions is shown. The resulting fluorous derivatives are separated by solid-phase extraction on fluorous silica gel (FSPE). The fluorous [1,2,4]triazoline-3,5-dione 10 reacted with most dienes within seconds or minutes.