We report a highly active single-site heterogeneous cobalt-catalyst based on a porous and robust pyridylimine-functionalized metal–organic frameworks (pyrim-MOF) for chemoselective borylation of arene and benzylic C–H bonds. The pyrim-MOF having UiO-68 topology, constructed from zirconium-cluster secondary building units and pyridylimine-functionalized dicarboxylate bridging linkers, was metalated with CoCl2 followed by treatment of NaEt3BH to give the cobalt-functionalized MOF-catalyst (pyrim-MOF-Co). Pyrim-MOF-Co has a broad substrate scope, allowing the C–H borylation of halogen-, alkoxy-, alkyl-substituted arenes as well as heterocyclic ring systems using B2pin2 or HBpin (pin = pinacolate) as the borylating agent to afford the corresponding arene- or alkyl-boronate esters in good yields. Pyrim-MOF-Co gave a turnover number (TON) of up to 2500 and could be recycled and reused at least 9 times. Pyrim-MOF-Co was also significantly more robust and active than its homogeneous control, highlighting the beneficial effect of active-site isolation within the MOF framework that prevents intermolecular decomposition. The experimental and computational studies suggested (pyrim•−)­CoI(THF) as the active catalytic species within the MOF, which undergoes a mechanistic pathway of oxidative addition, turnover limiting σ-bond metathesis, followed by reductive elimination to afford the boronate ester.

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Three new isostructural manganese coordination polymers, [Mn(H 2 O)(bpdc)] (1), [Mn(DMF)(bpdc)] (2), and [Mn-(DMSO)(bpdc)] (3) (bpdc = benzophenone-4,4′-dicarboxylate), have been successfully crystallized employing solvent variation. A single crystal X-ray diffraction study revealed that the three solids built of manganese polyhedron (square pyramidal in 1 and octahedral in 2 and 3) extended into two-dimensional sheets through manganese carboxylate coordination interaction. The packing of the layers, however, was greatly influenced through hydrogen bonding exerted by the coordinated solvent molecules (H 2 O, DMF, and DMSO) occupying the apical position of the manganese polyhedron. Low-temperature antiferromagnetic interactions arising due to coupling between the adjacent Mn 2+ ions showed a strong correlation with the variation in the packing of the layers. First-principles calculations of the electronic structures of the solids in terms of singlet (S = 0 with Noodleman's Broken Symmetry) and triplet (S = 1) states showed the superexchange interaction energies to be −0.24, −0.12, and −0.18 eV, respectively, for 1, 2, and 3; the magnetic exchange coupling variation is in correspondence with the decrease in H-bonding interaction holding the layers: H 2 O < DMSO < DMF. The paper also postulates a mechanistic pathway for the observed crystal packing in terms of supramolecular condensation of 1:1 manganese dicarboxylate complexes through a combination of coordination and H-bonding interactions.

Alkaline‐earth based coordination polymers (CPs) with rigid frameworks are promising candidates for future dielectrics. During our attempts to engineer new calcium and strontium dicarboxylates under solvothermal condition, we synthesized six CPs, namely, [Sr(BDC)(DMA)(H2O)] (1), [Ca(ABDC)(DMF)] (2), [Ca(ABDC)(DMA)2/3] (3), [Sr(ABDC)(DMF)] (4), [Sr(OBA)(MF)] (5) and {[Sr(FBA)(DMA)(H2O)].(DMA)(EtOH)(H2O)]} (6) [where, BDC=1,4‐benzenedicarboxylic acid, ABDC=2‐aminoterephthalic acid, OBA=4,4’‐oxybis(benzoic acid) and FBA=4,4’‐(hexafluoroisopropylidene)bis(benzoic acid)] and established its full structures using single crystal X‐ray crystallography. A significant structural feature of all the solids was the occurrence of rigid 1D columns made of metal carboxylate coordination. All the solids showed interesting dielectric behaviour and exhibited photoluminescence with blue or bluish‐green emission.

Six coordination polymers based on Mn(ii) and V-shaped ligand were successfully isolated and their dielectric as well as magnetic behaviours were investigated. The paper also discusses the growth of solids in terms of supramolecular aggregation.