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We have prepared and characterized three coordination polymers formulated as [Dy 2 (C 6 O 4 Cl 2 ) 3 (fma) 6 ] ⋅ 4.5fma (1) and [Dy 2 (C 6 O 4 X 2 ) 3 (fma) 6 ] ⋅ 4fma ⋅ 2H 2 O with X=Br (2) and Cl (3), where fma=formamide and C 6 O 4 X 2 2- =3,6-disubstituted-2,5-dihydroxy-1,4-benzoquinone dianion with X=Cl (chloranilato) and Br (bromanilato). Compounds 1 and 3 are solvates obtained with slow and fast precipitation methods, respectively. Compounds 2 and 3 are isostructural and only differ in the X group of the anilato ligand. The three compounds present (6,3)-gon two-dimensional hexagonal honey-comb structures. Magnetic measurements indicate that the three compounds show slow relaxation of the magnetization at low temperatures when a continuous magnetic field is applied, although with different relaxation times and energy barriers depending on X and the crystallisation molecules. Compounds 1-3 represent the first examples of anilato-based lattices with formamide and field-induced slow relaxation of the magnetization., (© 2024 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

We exploit the high versatility of the solvent ethylene glycol (eg = CH 2 OH-CH 2 OH) acting as a ligand with three different coordination modes: terminal (κ O ), chelate (κ 2 O,O' ), and bridge (1κ O ,2κ O' ) to prepare a novel family of six different coordination polymers with Dy III and three different anilato ligands (3,6-disubstituted-2,5-dihydroxy-1,4-benzoquinone dianion = C 6 O 4 X 2 2- , with X = H, Cl, and Br). With the X = H derivative (dhbq 2- ), we have prepared [Dy 2 (dhbq) 3 (eg) 2 (μ-eg)]·4eg·2H 2 O ( 1 ), a 3D diamond-like network with a chelate and bridging eg molecules. With the X = Cl derivative (chloranilato), we have prepared [Dy 2 (C 6 O 4 Cl 2 ) 3 (eg) 4 ]·2eg·H 2 O ( 2 ) and [Dy 2 (C 6 O 4 Cl 2 ) 3 (μ-eg)(H 2 O) 4 ]·2eg·7H 2 O ( 3 ). Compound 2 has a 2D (6,3)-gon brick-wall lattice and contains a chelate and a terminal eg molecule. Compound 3 has a 3D diamond-like topology as 1 , although now the chelate eg has been replaced by two water molecules. Finally, with the X = Br derivative (bromanilato), we have obtained [Dy 2 (C 6 O 4 Br 2 ) 3 (eg) 2 (CH 3 OH) 2 ]·2eg·4CH 3 OH ( 4 ), [Dy 2 (C 6 O 4 Br 2 ) 3 (eg) 4 ]·4eg ( 5 ), and [Dy 2 (C 6 O 4 Br 2 ) 3 (eg) 3 (H 2 O)]·2eg·H 2 O ( 6 ). Compound 4 has a 2D (6,3)-gon herringbone topology and contains a chelate eg and a MeOH molecule. Compounds 5 and 6 have a 2D (6,3)-gon brick-wall topology with a chelate and a terminal eg molecules (in 5 and in one of the two independent Dy centers of 6 ). The other Dy center in 6 has a chelate eg and a water molecule. All the compounds show slow relaxation of the magnetization at low temperatures (in compounds 1 , 2 , and 5 with no applied DC field). The magnetization of compounds 1 - 6 relaxes through Orbach and direct mechanisms when a DC field is applied and through an Orbach and/or quantum tunneling mechanism when no DC field is applied., Competing Interests: The authors declare no competing financial interest., (© 2023 American Chemical Society.)