Tridecanuclear [MnIII 5 LnIII 8 ] Complexes Derived from N-tButyl-diethanolamine: Synthesis, Structures, and Magnetic Properties

The synthesis, structures and magnetic properties of a family of heterometallic [MnIII 5 LnIII 8 (μ3-OH)12(L2)4(piv)12- (NO3)4(OAc)4]- (Ln = Pr, 2; Nd, 3; Sm, 4; Gd, 5; Tb, 6) aggregates are reported. The complexes were obtained from the direct reaction of N-tbutyldiethanolamine (H2L2) with Mn(OAc)2 3 4H2O and Ln(NO3)3 3 6H2O in the presence of pivalic acid (pivH) in MeCN under ambient conditions. Compounds 2-6 are isomorphous and crystallize in the monoclinic space group P21/n with four molecules in the unit cell. The complexes have a centrosymmetric tridecanuclear anionic core consisting of two distorted inner heterometallic [MnIIILnIII 3 (μ3-OH)4]8+ cubane subunits sharing a common Mn vertex flanked by four edge-sharing heterometallic [MnIIILnIII 2 (μ3-OH)4]5+ defect cubane units. Complexes 2-6 are the first high-nuclearity 3d-4f aggregates reported to date using tBu-deaH2 as ligand. These compounds show no evidence of slow relaxation behavior above 1.8 K, which appears to be the consequence of the very weak or non-existent magnetic interactions between the MnIII and LnIII ions resulting from the particular angles at the bridging oxygens

3,6-Connected Metal-Organic Frameworks Based on Triscarboxylate as a 3-Connected Organic Node and a Linear Trinuclear Co-3(COO)(6) Secondary Building Unit as a 6-Connected Node

The solvothermal reactions of cobalt(II) chloride hexahydrate and 1,3,5-benzenetribenzoic acid (H3BTB) in anhydrous N,N'-dimethylacetamide (DMA) at two different reaction temperatures and reactant concentrations led to two 3,6-connected metal-organic frameworks (MOFs) with different net topologies based on the ligand as a C-3 symmetric 3-connected organic node and the linear trinuclear cobalt carboxylate cluster, Co-3(COO)(6), as a 6-connected secondary building unit (SBU). MOF [Co-3(BTB)(2)(DMA)(4)], 1, with a linear trinuclear cobalt carboxylate cluster, Co-3(COO)(6), and with an inversion point symmetry with "compressed trigonal antiprismatic" 6-connectivity, is a two-dimensional (2-D) layered structure of a 3,6-connected kgd net topology. However, the same linear trinuclear cobalt carboxylate cluster, Co-3(COO)(6), with a 2-fold point symmetry with "compressed trigonal prismatic" 6-connectivity leads to the three-dimensional (3-D) network of 2, with an unprecedented 3,6-connected net topology with the point symbol (4(3))(2)(4(3).12(12)). The 2-D layered framework, 1, shows a significant sorption hysteresis for adsorbates with relatively strong interactions with the framework, such as N-2 and CO2.close191