Acetylenedicarboxylate as a linker in the engineering of coordination polymers and metal-organic frameworks: challenges and potential

Enhanced sorption in an indium-acetylenedicarboxylate metal-organic framework with unexpected chains of cis-μ-OH-connected {InO6} octahedra

Single crystals of the new metal-organic framework (MOF) In-adc (HHUD-4) were obtained through the reaction of linear acetylenedicarboxylic acid (H₂adc) with In(NO₃)₃·xH₂O as a racemic conglomerate in the chiral tetragonal space groups P4₃22 and P4₁22. Fundamentally different from other MOFs with linear linkers and trans-μ-OH-connected infinite {MO₆} secondary building units as in the MIL-53-type, the linear adc^2- linker leads to the formation of cis-μ-OH connected {InO₆} polyhedra, which have otherwise only been found before for V-shaped ligands, as in CAU-10-H. A far-reaching implication of this finding is the possibility that trans-μ-OH/straight MIL-53-type MOFs will have polymorphs of CAU-10-H cis-μ-OH/helical topology and vice versa. HHUD-4 is a microporous MOF with a BET surface area of up to 940 m² g^-1 and a micropore volume of up to 0.39 cm³ g^-1. Additionally, HHUD-4 features good adsorption uptakes of 3.77 mmol g^-1 for CO₂ and 1.25 mmol g^-1 for CH₄ at 273 K and 1 bar, respectively, and a high isosteric heat of adsorption of 11.4 kJ mol^-1 for H₂ with a maximum uptake of 6.36 mmol g^-1 at 77 K and 1 bar. Vapor sorption experiments for water and volatile organic compounds (VOCs) such as benzene, cyclohexane and n-hexane yielded uptake values of 135, 269, 116 and 205 mg g^-1, respectively, at 293 K. While HHUD-4 showed unremarkable results for water uptake and low stability for water, it exhibited good stability with steep VOC uptake steps at low relative pressures and a high selectivity of 17 for benzene/cyclohexane mixtures.

Synthesis and the Crystal Structure of a New Chiral 1D Metal-Organic Coordination Polymer Based on L-Prolineamide-Substituted Diarylacetylenedicarboxylic Acid Derivative

The new homochiral 1D metal-organic coordination polymer [Cu₂(EDPB)•H₂O]_n was synthesized starting from the original 3,3'-ethyne-1,2-diylbis[6-(L-prolylamino)benzoic acid] (H₄EDPB). The unique crystal structure of the new compound was established by powder X-ray diffraction. The [Cu₂(EDPB)•H₂O]_n system shows catalytic activity and enantioselectivity in a Henry reaction of p-nitrobenzaldehyde with nitromethane.

Application of Metal–Organic Framework in Diagnosis and Treatment of Diabetes

Diabetes-related chronic wounds are often accompanied by a poor wound-healing environment such as high glucose, recurrent infections, and inflammation, and standard wound treatments are fairly limited in their ability to heal these wounds. Metal–organic frameworks (MOFs) have been developed to improve therapeutic outcomes due to their ease of engineering, surface functionalization, and therapeutic properties. In this review, we summarize the different synthesis methods of MOFs and conduct a comprehensive review of the latest research progress of MOFs in the treatment of diabetes and its wounds. State-of-the-art in vivo oral hypoglycemic strategies and the in vitro diagnosis of diabetes are enumerated and different antimicrobial strategies (including physical contact, oxidative stress, photothermal, and related ions or ligands) and provascular strategies for the treatment of diabetic wounds are compared. It focuses on the connections and differences between different applications of MOFs as well as possible directions for improvement. Finally, the potential toxicity of MOFs is also an issue that we cannot ignore.