Cyanide-Bridged Rope-like Chains Based on Trigonal-Bipyramidal [Fe 2 Cu 3 ] Subunits.

Extending a selected cyanometalate block into a higher dimensional framework continues to present intriguing challenges in the fields of chemistry and material science. Here, we prepared two rope-like chain compounds of {[(Tp* Me )Fe(CN) 3 ] 2 Cu 2 X 2 (L)}·sol ( 1 , X = Cl, L = (MeCN) 0.5 (H 2 O/MeOH) 0.5 , sol = 2MeCN·1.5H 2 O; 2 , X = Br, L = MeOH, sol = 2MeCN·0.75H 2 O; Tp* Me = tris(3, 4, 5-trimethylpyrazole)borate) in which the cyanide-bridged trigonal-bipyramidal [Fe 2 Cu 3 ] subunits were linked with the adjacent ones via two vertex Cu(II) centers, providing a new cyanometallate chain archetype. Direct current magnetic study revealed the presence of ferromagnetic couplings between Fe(III) and Cu(II) ions and uniaxial anisotropy due to a favorable alignment of the anisotropic tricyanoiron(III) units. Moreover, compound 1 exhibits single-chain magnet behavior with an appreciable energy barrier of 72 K, while 2 behaves as a metamagnet, likely caused by the subtle changes in the interchain interactions.