Synthesis and characterization of light-fluorous NHC-ligands and their palladium complexes

Abstract

Light-fluorous ponytails containing perfluoro-n-propyl, perfluoro-n-butyl and perfluoro-t-butoxy groups were used to synthesize light-fluorous α-olefins, branched dialkyl iodides, alkyl triflates, alkyl imidazoles, and dialkyl imidazolium salts. The latter were used to prepare two light-fluorous N,N’-dialkyl-imidazole-2-ylidene diiodo palladium(II) complexes. The fluorous partition coefficients of the light-fluorous olefins, iodides, and triflates were measured in perfluoro(methylcyclohexane)/toluene biphasic system, which revealed that the shorter and environmentally friendlier perfluoroalkyl chains of the light-fluorous ponytails results in lower fluorous partition coefficients, especially as the number of methylene groups increases.