The solubilities of the ternary systems Ln(ClO~4)~3-PCBAAP-H~2O (Ln=La, Yb) at 30℃ were determined, and the incongruent compounds, Ln(PCBAAP)~4(ClO~4)~3·nH~2O(Ln=La, n=6; Ln=Yb, n=2) were discovered in the systems. Based on the results of solubilities, the series compounds, Ln(PCBAAP)~4(ClO~4)~3·nH~2O(Ln=La, n=6; Ln=Pr, Nd, Sm, Gd, Yb, n=2) were synthesized by means of phase equilibrium method. The compounds were characterized by chemical analysis, elemental analysis, IR spectra, TG-DTG analysis, XRD and density determination, respectively.

Key words: ANTIPYRINU, SOLUBILITY, PHASE EQUILIBRIUM, BENZOYL GROUP, WATER