Thermal reaction products of copper(II) hydrogen salicylate tetrahydrate and copper(II) benzoate trihydrate in the solid state at various water vapor pressures

On thermal decomposition of copper(II) hydrogen salicylate tetrahydrate Cu(Hsal)2·4H2O(sal=C6H4OHCOO)[1], an anhydrous monomer, Cu(Hsal)2 [2] and a dimer Cu2(Hsal)4 [3] were obtained at water vapor pressures under 26.0mmHg and above 143 mmHg, respectivery. In the case of dehydration of copper(II) benzoate trihydrate Cu(C6H5COO)2·3H20 [4], an anhydrous dimer [6] was prepared at water vapor pressures under 143 mmHg on the other hand, a new anhydrous complex [7], which is different from [6] was obtained above 273mmHg. Moreover, an amorphous anhydrous complex [5] was obtained at approximately 0mmHg. For both copper(II) hydrogen salicylate and copper(II) benzoate complexes, different anhydrous complexes were formed at various water vapor pressures. The fact suggests that a gaseous phase-solid phase reaction plays an important role.