Halide ions complex and deprotonate dipicolinamides and isophthalamides: Assessment by mass spectrometry and UV-visible spectroscopy

摘要

The F~-, Cl~-, and Br~- binding selectivity of bis(p-nitroanilide)s of dipicolinic and isophthalic acids was studied by using competitive electrospray mass spectrometry and UV-Visible spectroscopy. Both hosts prefer binding Cl~- over either F~- or Br ~-. Host deprotonation was observed to some extent in all experiments in which the host was exposed to halide ions. When F~- was present, host deprotonation was often the major process, whereas little deprotonation was observed by Cl~- or Br~-, which preferred complexation. A solution of either host changed color when mixed with a F~-, H _2PO_4~-, di- or triphenylacetate solution.