Synthesis and fluorophilicity of compounds with tris(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)silyl substituent

Abstract

Abstract A series of new highly fluorous compounds with tris(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)silyl substituent was synthesized starting from 3-halopropyltris(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)silanes. The series can be divided into three subgroups based on the potential use of theses compounds: (i) cyclopentadienyl transition metal complexes and N-ligands, (ii) synthons for azide-alkyne [3+2] cycloaddition, (iii) imidazolium-type ionic liquids. Partition coefficients between fluorous and organic phases in a standard system perfluoro(methylcyclohexane)/toluene were measured using various methods. Both new and several similar previously prepared compounds were included. Gravimetry and 19 F NMR spectroscopy were used for all the compounds whereas gas chromatography and AAS/AES spectroscopy were used where appropriate. Generally, consistent values were obtained by different methods. The partition coefficients of the compounds ranged from 10 to 100 with the exception of cyclopentadienyl complexes, where the partition coefficients were an order of magnitude lower, and ionic liquids, where the partition coefficients were higher than 100. In some cases the limits of detection of ionic liquids in the organic phase were reached, at the same time they were well soluble in the fluorous phase.