Thermal stability of pyridine base complexes of cadmium chloride

The heat of decomposition of a series of crystalline pyridine base (Rpy) co mplexes of cadmium chloride was determined by means of differential scannin g calorimetry, where the complexes were bis(pyridine base) complexes, CdCl2 . 2Rpy (Rpy = pyridine and 4-methyl-, 3-methyl-, 4-acetyl- and 4-cyanopyrid ine) and mono(pyridine base) complexes, CdCl2. Rpy (Rpy = 2-methyl- and 2-e thylpyridine). The heats of dissolution of the pyridine base complexes, cad mium chloride CdCl2, and pyridine bases in a non-polar aprotic solvent, 1,2 -dichloroethane, containing tetrabutylammonium chloride were determined by a calorimetry. The stability of the crystalline complexes is discussed in c onnection with the heat of dissolution and reaction of the complexes in sol ution. The stability of the complexes is explained by various interactions, such as the basicity and steric hindrance of the pyridine bases and the in termolecular interaction between the complexes.