The Impact of Perfluoroalkyl Groups on Phosphane Basicity

This study employed computational methods to investigate the basicity of a series of polyfluorinated phosphanes. Results revealed an exceptionally low basicity, with the computed p<i>K</i>_aH values in acetonitrile approaching -30, a value significantly lower than anticipated. The good agreement between the SMD and COSMO-RS methods provided confidence in the reliability of these values. This unexpected behavior challenges conventional perceptions of phosphane basicity and deepens our understanding of the electronic effects of fluorination. The findings hold important implications for catalysis, ligand design, and main-group chemistry, where a precise comprehension of phosphane electronic properties is crucial. p<i>K</i>_aH(MeCN) values, gas-phase basicities, and steric parameters are reported for 14 phosphanes.