Ionothermal Synthesis and Magnetic Studies of Novel Two-Dimensional Metal−Formate Frameworks

Five novel two-dimensional frameworks containing formate-bridged metal-centered octahedra are synthesized ionothermally from two ionic liquids previously unused as solvents in hybrid synthesis, 2-hydroxyethylammonium (HEA) formate, and 1-hydroxy-3-proplyammonium (HPA) formate. Templating effects of the cation from each ionic liquid drive the formation of different structures. [NH3C2H4OH]2[M(CHO2)4] (1: M = Co, 2: M = Ni) exhibit the same stoichiometry and connectivity as their manganese analogue (3: M = Mn), but the manganese form exhibits a different topology from 1 and 2. [NH3C3H6OH][M(CHO2)3(H2O)] (4: M = Co, 5: M = Mn) were synthesized using the HPA formate ionic liquid with a metal−formate connectivity related to those of 1−3. Canted antiferromagnetic ordering occurs at low temperatures (1: TN = 7.0 K, 2: TN = 4.6 K, 3: TN = 8.0 K, 4: TN = 7.0 K, 5: TN = 9.2 K), similar to the magnetic properties previously reported for other metal−formate hybrid materials.