Two novel pyrimidine derivatives have been synthesized and their structures have been confirmed by IR, 1HNMR
andmass spectral data. The dissociation constants of these two compounds; 4-(naphthalen-1-yloxy)-N-(p-tolyl)
pyrimidin-2-amine (TP-1) and N-(4-fluoro phenyl)-4-(naphthalen-1-yloxy) pyrimidin-2-amine (FP-1) were
studied in methanol/DMF - water (60:40 v/v) solvent systems at different temperatures ranging from 25 °C to
45 °C at a 10 °C interval using the Calvin–Bjerrum pH titration method.