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A novel Zn dipyrazolate metal‐organic framework (MOF), Zn(azbpz) (azbpz2−=4,4′‐azobis(3,5‐dimethylpyrazolate), has been synthesized and structurally characterized using micro‐crystal electron diffraction. The framework contains chain‐type secondary building units comprised of tetrahedral Zn2+ ions bridged by pyrazolate groups, resulting in guest‐accessible channels lined with methyl and azo functional groups. CO2, C2H2, C2H4, C2H6, C3H6, and C3H8 gas adsorption isotherms were measured to investigate the potential of Zn(azbpz) as an adsorbent for selective separation of binary gas mixtures. The data reveal selective adsorption of acetylene over CO2, and column breakthrough experiments demonstrate good performance for C2H2/CO2 separation. [ABSTRACT FROM AUTHOR]

We describe the preparation, dynamic, assembly characteristics of vase-shaped basket 1 3- along with its ability to form an inclusion complex with anticancer drug mitoxantrone in abiotic and biotic systems. This novel cavitand has a deep nonpolar pocket consisting of three naphthalimide sides fused to a bicyclic platform at the bottom while carrying polar glycines at the top. The results of 1 H Nuclear Magnetic Resonance (NMR), 1 H NMR Chemical Exchange Saturation Transfer (CEST), Calorimetry, Hybrid Replica Exchange Molecular Dynamics (REMD), and Microcrystal Electron Diffraction (MicroED) measurements are in line with 1 forming dimer [1 2 ] 6- , to be in equilibrium with monomers 1 (R) 3- (relaxed) and 1 (S) 3- (squeezed). Through simultaneous line-shape analysis of 1 H NMR data, kinetic and thermodynamic parameters characterizing these equilibria were quantified. Basket 1 (R) 3- includes anticancer drug mitoxantrone (MTO 2+ ) in its pocket to give stable binary complex [MTO⊂1] - (K d =2.1 μM) that can be precipitated in vitro with UV light or pH as stimuli. Both in vitro and in vivo studies showed that the basket is nontoxic, while at a higher proportion with respect to MTO it reduced its cytotoxicity in vitro. With well-characterized internal dynamics and dimerization, the ability to include mitoxantrone, and biocompatibility, the stage is set to develop sequestering agents from deep-cavity baskets., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

A novel Zn benzotriazolate metal-organic framework (MOF), [Zn 9 (OAc) 6 (bbtm) 6 ] ( 1 , bbtm 2- = bis(benzotriazolyl)methanone, OAc - = acetate), has been synthesized and structurally characterized using micro-crystal electron diffraction. The framework contains 12-connected nonanuclear Zn clusters with Zn-OAc groups separated by short intercluster Zn···Zn distances of 6.06 Å. Postsynthetic OAc - /OH - ligand exchange followed by thermal activation generates 1a-OH , which adsorbs CO 2 at very low pressures (1.37 mmol/g at 2.5 mbar) and requires an unusually high desorption temperature (>160 °C). Diffuse reflectance IR Fourier transform spectroscopy (DRIFTS) and density functional theory (DFT) calculations have been used to interrogate the CO 2 binding mechanism in 1a-OH . The formation of unsymmetric bridging carbonate ligands within the Zn···Zn pockets accompanied by strong hydrogen bonding of the carbonate with a neighboring zinc aqua ligand explains the remarkably strong CO 2 affinity of 1a-OH .