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Inducing, understanding, and controlling the flexibility in metal-organic frameworks (MOFs) are of utmost interest due to the potential applications of dynamic materials in gas-related technologies. Herein, we report the synthesis of two isostructural two-dimensional (2D) interweaving zinc(II) MOFs, TMU-27 [Zn(bpipa)(bdc)] and TMU-27-NH 2 [Zn(bpipa)(NH 2 -bdc)], based on N , N '-bis-4-pyridyl-isophthalamide (bpipa) and 1,4-benzenedicarboxylate (bdc) or 2-amino-1,4-benzenedicarboxylate (NH 2 -bdc), respectively. These frameworks differ only by the substitution at the meta-position of their respective bdc groups: an H atom in TMU-27 vs an NH 2 group in TMU-27-NH 2 . This difference strongly influences their respective responses to external stimuli, since we observed that the structure of TMU-27 changed due to desolvation and adsorption, whereas TMU-27-NH 2 remained rigid. Using single-crystal X-ray diffraction and CO 2 -sorption measurements, we discovered that upon CO 2 sorption, TMU-27 undergoes a transition from a closed-pore phase to an open-pore phase. In contrast, we attributed the rigidification in TMU-27-NH 2 to intermolecular hydrogen bonding between interweaving layers, namely, between the H atoms from the bdc-amino groups and the O atoms from the bpipa-amide groups within these layers. Additionally, by using scanning electron microscopy to monitor the CO 2 adsorption and desorption in TMU-27, we were able to establish a correlation between the crystal size of this MOF and its transformation pressure.

A vapor-assisted synthesis method was developed for the metal-organic framework (MOF) HKUST-1 in both powder and film format. The use of a solvent template supplied from the vapor phase is essential to form the framework under these conditions. Chemical vapor deposition of HKUST-1 films (MOF-CVD) results in smooth films that show the expected adsorption behavior. Interestingly, the HKUST-1 films obtained this way show a (111) preferred crystallographic orientation.

Composites formed by a metal-organic framework (MOF) and an ionic liquid (IL) are potentially interesting materials for applications ranging from gas separation to electrochemical devices. Consequently, there is a need for robust and low-cost preparation procedures that are compatible with the desired applications. We herein report a solvent-free, one-step, and vapor-based ship-in-bottle synthesis of the IL@MOF composite 1-butyl-3-methylimidazolium bromide@ZIF-8 in powder and thin film forms. In this approach, volatile IL precursors evaporate and subsequently adsorb and react within the MOF cages to form the IL.

Two series of neutral luminescent pentafluorophenyl cycloplatinated(II) complexes [Pt(C^N)(C 6 F 5 )L] [C^N = C-deprotonated 2-phenylpyridine (ppy; a), 2-(2,4-difluorophenylpyridine (dfppy; b)] incorporating dimethyl sulfoxide [L = DMSO for 1 (1a reported by us in ref (14) )] or biocompatible phosphine [L = PPh 2 C 6 H 4 COOH (dpbH; 2), PPh 2 C 6 H 4 CONHCH 2 COOMe (dpbGlyOMe; 3), P(C 6 H 4 SO 3 Na) 3 (TPPTS; 4)] ligands have been prepared and characterized and their optical properties studied. Their cytotoxic activities against tumor A549 (lung carcinoma), HeLa (cervix carcinoma), and nontumor NL-20 (lung epithelium) cell lines, as well as the ability to interact with DNA (plasmid pBR322), were evaluated. Complexes 2 exhibit higher cytotoxicity (IC 50 3.89-20.29 μM) than compounds 1 (9.03-20.50 μM), whereas the activities of complexes 3 and 4 are negligible. All cytotoxic complexes show low selective toxicities toward cancer cells. Interestingly, except 1a, these complexes do not show evidence of DNA intercalation. Along the same lines, fluorescence costaining with Hoechst (2,5'-bi-1 H-benzimidazole, 2'-(4-ethoxyphenyl)-5-(4-methyl-1-piperazinyl), a nuclear DNA stain) reveals that all complexes easily internalize, being mainly localized in the cytoplasm. In order to deepen the mechanism of biological action, the effect of the most cytotoxic complex 2b toward the dynamics of tubulin was explored. This complex displays tubulin depolymerization activity, exhibiting more potent inhibition of microtubule formation in A549 than in HeLa cells, in accordance with its higher antiproliferative activity (IC 50 6.98 vs 12.45 μM), placing this complex as a potential antitubulin agent.

We report design and structural characterization of six new coordination polymers fabricated from PbCl 2 and a series of closely related bis-pyridyl ligands L I and HL II -HL VI , namely, [Pb 2 (L I )Cl 4 ] n , [Pb(HL II )Cl 2 ] n ·nMeOH, [Pb(HL III )Cl 2 ] n ·0.5 nMeOH, [Pb 2 (L IV )Cl 3 ] n , [Pb(HL V )Cl 2 ] n , and [Pb 3 (L VI ) 2 Cl 4 ] n ·nMeOH. The topology of the obtained networks is dictated by the geometry of the organic ligand. The structure of [Pb 2 (L I )Cl 4 ] n is constructed from the [PbCl 2 ] n two-dimensional (2D) sheets, linked through organic linkers into a three-dimensional framework, which exhibits a unique binodal 4,7-connected three-periodic topology named by us as sda1. Topological analysis of the 2D metal-organic sheet in [Pb(HL II )Cl 2 ] n ·nMeOH discloses a binodal 3,4-connected layer topology, regardless of the presence of tetrel bonds. A one-dimensional (1D) coordination polymer [Pb(HL III )Cl 2 ] n ·0.5 nMeOH is considered as a uninodal 2-connected chain. The overall structure of [Pb 2 (L IV )Cl 3 ] n is constructed from dimeric tetranuclear [Pb 4 (μ 3 -L IV -κ 6 N:N':N″:μ 3 -O) 2 (μ 4 -Cl)(μ 2 -Cl) 2 ] 3+ cationic blocks linked in a zigzag manner through bridging μ 2 -Cl - ligands, yielding a 1D polymeric chain. Topological analysis of this chain reveals a unique pentanodal 3,4,4,5,6-connected chain topology named by us as sda2. The structure of [Pb(HL V )Cl 2 ] n exhibits a 1D zigzaglike polymeric chain. Two chains are further linked into a 1D gridlike ribbon through the dimeric [Pb 2 (μ 2 -Cl) 2 Cl 2 ] blocks as bridging nodes. With the bulkiest ligand HL VI , a 2D layered coordination polymer [Pb 3 (L VI ) 2 Cl 4 ] n ·nMeOH is formed, which network, considering all tetrel bonds, reveals a unique heptanodal 3,3,3,3,4,5,5-connected layer topology named by us as sda3. Compounds [Pb 2 (L I )Cl 4 ] n , [Pb 2 (L IV )Cl 3 ] n , and [Pb(HL V )Cl 2 ] n were found to be emissive in the solid state at ambient temperature. While blue emission of [Pb 2 (L I )Cl 4 ] n is due to the ligand-centered transitions, bluish-green and white luminescence of [Pb 2 (L IV )Cl 3 ] n and [Pb(HL V )Cl 2 ] n , respectively, was assigned to ligand-to-metal charge transfer mixed with metal-centered excited states. Molecular as well as periodic calculations were additionally applied to characterize the obtained polymers.