Solid supported active esters as linkers: modification of reactivity using iron carbonyl complexes

The reactivity of three polymer-bound cyclohexadienoic acid active esters was modified by complexation with iron tricarbonyl in order to evaluate their potential use as linker systems for solid phase chemistry. The best results were obtained with the tetrafluorophenol ester, which was slowly cleaved when 1 equiv of amine was used, but could be rapidly cleaved with up to 94% yield when the amount of nucleophile was increased.