Synthesis, Crystal Structures, and Thermal Properties of Protic Metal-Containing Ionic Liquids, Diethanolammonium Halometallates: (HOCH2CH2)2NH2FeCl4 and ((HOCH2CH2)2NH2)2CoCl4

Protic metal-containing ionic liquids with the diethanolammonium cation (HO–CH 2 –CH 2 ) 2 (DEAH + ) and anions and (DEAHFeCl 4 ( I ), (DEAH) 2 CoCl 4 ( II )) are synthesized. The crystal structures of compounds I and II are determined by X-ray structure analysis (CIF files CCDC nos. 1957208 ( I ) and 1957189 ( II )). Compound I has a layered structure. The layer consists of the DEAH + cations with the disordered system of hydrogen bonds and attached anions. The structure of compound II represents a three-dimensional framework consisting of the DEAH + cations and anions linked by hydrogen bonds. The thermal analysis shows that the melting points of compounds I (45°С) and II (55°С) are lower than 100°С, the enthalpy of melting of compound I is higher than that of compound II , and the decomposition temperature of compound II (210°С) is higher than that of compound I (128°C).