SOLUBILITIES OF ORGANOBORON COMPOUNDS IN ORGANIC-SOLVENTS .2. SOLID-LIQUID EQUILIBRIA OF SOME PYRAZABOLES PLUS N-ALKANOLS

The solubilities of some pyrazaboles (pyrazabole, 4,4,8,8-tetraethylpy razabole, and 4,4,8,8-tetrapropylpyrazabole) in n-alkanols (1-butanol, 1-hexanol, 1-octanol, 1-decanol and 1-dodecanol) have been determined at temperatures ranging from the melting point of the solute to 273 K . Two correlation methods were applied: the Wilson and the UNIQUAC ASM [associated-solution model]. The average r.m.s. deviations of the sol ubility temperatures for all measured data were 1.8 K and 2.0 K for th e Wilson and the UNIQUAC ASM model respectively. The best solubility c orrelation for alcohols was obtained with the UNIQUAC ASM KW equation, with the association constants as an adjustable parameter. In the cal culations, the existence of one solid-solid first-order phase transiti on of 4,4,8,8-tetraethylpyrazabole has also been taken into considerat ion.