condensation reactions using various fluorous Mukaiyama reagents, including a novel medium-fluorous strategy, is described. A Mukaiyama reagent bearing a medium-fluorous content tag, between 40 and 60% fluorine by weight, was prepared and examined in ester and amide-forming condensation reactions. At the end of the reactions, the fluorous pyridone by-product was effectively separated from non-fluorous components
The observed rate enhancement for the condensation reaction between 2-phenyl benzoic acid and isopropanol mediated by fluorous Mukaiyama reagents is described. It is shown that Mukaiyama reagents bearing a fluorous tag increase the reaction rate considerably when compared to their non-fluorous tagged counterpart. Furthermore, it is observed that the longer the fluorous chain, the higher the activity of the Mukaiyama reagent. (C) 2009 Elsevier Ltd. All rights reserved.