Water-soluble porphyrins have garnered significant attention due to their broad range of applications in biomedicine, catalysis, and material chemistry. In this work, water-soluble platinum(ii) and palladium(ii) complexes with porphyrins bearing ethyl phosphonate substituents, namely, Pt/Pd 10-(ethoxyhydroxyphosphoryl)-5,15-di(p-carboxyphenyl)porphyrins (M3m, M = Pt(ii), Pd(ii)) and Pt/Pd 5,10-bis(ethoxyhydroxyphosphoryl)-10,20-diarylporphyrins (M1d-M3d; aryl = p-tolyl (1), mesityl (2), p-carboxyphenyl (3)), were synthesized by alkaline hydrolysis of the corresponding diethyl phosphonates M6m and M4d-M6d. NMR, UV-vis, and fluorescence spectroscopy revealed that the mono-phosphonates M3m tend to form aggregates in aqueous media, while the bis-phosphonates M3d exist predominantly as monomeric species across a wide range of concentrations (10-6-10-3 M), ionic strengths (0-0.81 M), and pH values (4-12). Single-crystal X-ray diffraction studies of the diethyl phosphonates Pt6d and Pd6d revealed that pi-pi stacking of the aromatic macrocycles is sterically hindered in the crystals, providing a rationale for the low degree of solution aggregation observed for ethyl phosphonate M3d. Photophysical studies of M3m and M1d-M3d demonstrated that these compounds are phosphorescent and generate singlet oxygen in aqueous solutions. Pd(ii) complex Pd3d is an excellent photocatalyst for the oxidation of sulfides using di-oxygen in a solvent mixture (MeCN/H2O, 4 : 1 v/v). Under these conditions, various alkyl and aryl sulfides were quantitatively converted into the desired sulfoxides. For the oxygenation of mixed alkyl-aryl sulfides, Pd3d outperforms Pd(ii) meso-tetrakis(p-carboxyphenyl)porphyrin (PdTCPP). This photocatalyst can be recycled and reused to afford sulfoxides with no loss of product yield.

We report design and synthesis of novel picket-fence phthalocyanines to access the ruthenium(II) complexes carrying di-(1R,2S,5R)-menthoxy substituted aryloxy-groups. Owing to bulkiness of such groups located either at peripheral (β) or non-peripheral (α) positions, they are nearly orthogonal to the plane of the phthalocyanine thus creating a chiral environment around the metal center. This orthogonality was supported by X-ray analysis of corresponding phthalonitrile precursors (86.0° and 81.4° angles between the planes of aromatic moieties for α- and β-substituted phthalonitriles, respectively). As a proof of concept, the synthesized complexes were investigated as catalysts in a benchmark reaction of the cyclopropanation of styrene by ethyl diazoacetate. While the β-substituted complex showed very low enantioselectivity, the α-substituted analogue afforded a moderate asymmetric induction towards ethyl (1S,2R)-2-phenylcyclopropane-1-carboxylate. This result emphasizes the importance of appropriate arrangement of the chiral groups relative to the phthalocyanine catalytic center and provides guidelines for further elaboration of phthalocyanine catalysts for asymmetric transfer of carbenes.

For decades, the inherently reflective nature of metallic electromagnetic (EM) shields and their induced secondary EM pollution have posed significant challenges for sensitive electronics. While numerous efforts have been made to develop superior EM shielding systems, the issue of reflection dominancy in metallic substrates remains unresolved. Herein, we addressed this long-lasting obstacle by pairing metallic shields with ultra-lightweight (density of 3.12-3.40 mg cm-3) elastic anti-reflection aerogels, altering their shielding mechanism from dominant reflection (reflectance >0.8) to absorption (absorbance >0.7) by trapping EM waves inside the aerogel. The aerogel EM traps were generated using interfacial complexation, yielding engineerable filamentous liquid structures. These served as templates for aerogel creation through a follow-up process of freezing and lyophilization. The engineerable lossy medium of aerogels benefits from a multi-scale porous construct with the combined action of dielectric and conduction losses, highly dissipating the EM waves and minimizing the reflections. Notably, declining the diameter of aerogel filaments promoted its absorption dominancy, rendering it a potent dissipating medium for EM waves. Pairing a metallic substrate with filamentous aerogel EM traps has resulted in an exceptionally effective absorption-dominant shielding system, achieving absorbance levels between 0.70-0.81. This system offers a shielding effectiveness of 53-89 dB within the X-band frequency range. This innovation addresses a persistent issue in shielding science related to the reflective characteristics of metallic substrates, effectively inhibiting their induced EM reflections.

Noncovalent interactions form the basis of matter and life yet are difficult to characterize. Here we devised a platform strategy to systematically build noncovalent interactions with selective chemical groups into precisely designed configurations by using metal-organic frameworks (MOF) as the molecular scaffold. Using the vibrational Stark effect benchmarked against computer models, we found the electric field provides a unifying metric for quantifying diverse noncovalent interactions in MOFs and solutions. By synthetically making and spectroscopically testing a collection of noncovalent interactions using a nitrile probe, we identified stabilizing fields as strong as -123 MV/cm produced additively by multiple hydrogen bonds, an unusual destabilizing field of +6 MV/cm between antiparallel dipoles , anomalous hydrogen-bond blueshifts as large as 34 cm-1, and unique solvation under nanoconfinement. This method for making and testing noncovalent interactions opens new avenues for exploring the universe of noncovalent interactions.

Contextualising the promise of nanoscience and nanotechnology for water pollution remediation.

The ability to finely tune/balance the structure and rigidity of enzymes to realize both high enzymatic activity and long-term stability is highly desired but highly challenging. Herein, we propose the concept of the "silicazyme", where solid inorganic silica undergoes controlled hybridization with the fragile enzyme under moderate conditions at the single-enzyme level, thus enabling simultaneous structure augmentation, long-term stability, and high enzymatic activity preservation. A multivariate silicification approach was utilized and occurred around individual enzymes to allow conformal coating. To realize a high activity-stability trade-off the structure flexibility/rigidity of the silicazyme was optimized by a component adjustment ternary (CAT) plot method. Moreover, the multivariate organosilica frameworks bring great advantages, including surface microenvironment adjustability, reversible modification capability, and functional extensibility through the rich chemistry of silica. Overall silicazymes represent a new class of enzymes with promise for catalysis, separations, and nanomedicine.

Evolutionary selection in nature has led to hierarchical structuring as a fundamental optimization strategy for biological structures, maximizing functional performance while minimizing resource usage. Precise hierarchical organization of natural materials over a wide range of length scales gives rise to unique synergistic properties that could not be achieved by single components. Despite the clear advantages offered by hierarchically structuring matter, mastering hierarchical control based on the current synthetic toolbox is still a challenge. In this review, some recent advancements in the fabrication of hierarchical metal organic framework (MOF) materials are highlighted and the advantages that arise due to different kinds of MOF hierarchy are critically analyzed. The special focus of the review lies in highlighting the applications where MOF hierarchical materials can be most impactful and describing characterization techniques currently at the disposal of scientists for the precise characterization of MOF hierarchical structures across all length scales. Finally, the intent is to inspire reticular chemists to master hierarchical control of MOF materials so as to fully utilize the advantages MOFs offer for various applications.

Metal-organic frameworks (MOFs) are promising next-generation crystalline porous materials with exceptional structural, chemical, and application diversity. Since their discovery, the reticular tunability and physiochemical properties of MOFs have been studied and carefully manipulated to make them suitable for a wide variety of applications. After decades of research, these materials are moving from the benchtop to commercial, industrial-scale production. Although MOFs are now widely explored, the overall environmental impacts of these emerging materials are still underexplored. In this work, the first example of overall assessment of ten industrially produced and widely explored MOFs considering 18 diverse environmental impact categories such as global warming potential, fossil resource scarcity, water consumption, ecotoxicity, etc. via cradle-to-gate life cycle assessment is presented. Importantly, this study presents a comprehensive comparison between different synthetic methods of each MOF and compiles the environmental impacts associated only with the individual "synthesis" or "washing" steps. This study highlights the critical importance of using of green solvents over organic to reduce the overall environmental footprint. By identifying the synthetic drawbacks associated with different methods, this work provides a blueprint for the sustainable design and required future development of MOF synthesis. This work represents a pioneering study of systematic and comprehensive environmental impact assessment of 10 of the most widely studied and commercially available metal-organic framework (MOFs), using 18 environmental impact categories. image

The redox state of the phthalocyanine in sandwich lanthanide complexes is crucial for their applications. In this work, we demonstrate that the cation-induced supramolecular assembly of crown-substituted phthalocyanine lanthanide complexes Ln[(15C5)4Pc]2 can be used to control the redox state of the ligand simultaneously with the coordination sphere of the central metal. We achieve unprecedented redox switching of phthalocyanine ligands in a double-decker Gd(III) complex, resulting from the intramolecular inclusion of potassium cations between the decks with simultaneous twisting of the ligands (the skew angle between them decreases from 44.61° to 0.21°). Such a structural change leads to an increase in the deck to deck distance and drastically facilitates ligand reduction. It was demonstated that this process is anion dependent. Thus, only potassium salts of weak acids (KOPiv, KOAc) induce intramolecular inclusion of cations with redox switching in contrast to salts of strong acids (KBr, KOPic, KSCN and KPF6), where such a redox process does not occur. This breakthrough opens new avenues for controlling the electrochromic properties of phthalocyanines, along with other properties, such as electrical conductivity, optics, etc.

The possibility of the formation of supramolecular hybrids based on two photosensitizers, an octahedral molybdenum(II) iodide cluster with six terminal isonicotinate ligands (Bu 4 N) 2 [{Mo 6 I 8 }(OOC–C 5 H 4 N) 6 ] (PyMoC, C) and A 4 -type zinc(II) porphyrin (ZnTPP, P), has been demonstrated. Spectrophotometric and NMR titration methods have shown that the formation of CP n complexes ( n = 1–6) occurs in solutions of noncoordinating chlorinated solvents due to the formation of metal–N-ligand coordination bonds between the components. The use of an octahedral cluster as a hexatopic N-ligand and the lability of the Zn···N Py bonds together lead to the formation of a series of CP n complexes ( n = 1–6), which are in dynamic equilibrium in solution. Nevertheless, conditions have been selected to isolate single crystals of individual forms CP 4 + 2 and CP 6 + 2 , and their structures have been determined by X-ray diffraction analysis. The PyMoC cluster turns out to coordinate four or six ZnTPP molecules, respectively, while both structures contain two “extramolecules” of zinc(II) porphyrin bound to the cluster via hydrogen bonds involving the oxygen atoms of the isonicotinate groups and protons of water axially coordinated to the porphyrin metal center.

Angewandte Chemie International EditionVolume 62, Issue 22 e202382211 Graphical AbstractFree Access Graphical Abstract: Angew. Chem. Int. Ed. 22/2023 First published: 12 May 2023 https://doi.org/10.1002/anie.202382211AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Volume62, Issue22May 22, 2023e202382211 RelatedInformation

As the majority of known metal-organic frameworks (MOFs) possess anisotropic crystal lattices and thus anisotropic physicochemical properties, a pressing practical challenge in MOF research is the establishment of robust and simple processing methods to fully harness the anisotropic properties of the MOFs in various applications. We address this challenge by applying an E-field to precisely align MIL-88A microcrystals and generate MIL-88A@polymer films. Thereafter, we demonstrate the impact of MOF crystal alignment on the actuation properties of the films as a proof of concept. We investigate how different anisotropies of the MIL-88A@polymer films, specifically, crystal anisotropy, particle alignment, and film composition, can lead to the synergetic enhancement of the film actuation upon water exposure. Moreover, we explore how the directionality in application of the external stimuli (dry/humid air stream, water/air interface) affects the direction and the extent of the MIL-88A@polymer film movement. Apart from the superior water-driven actuation properties of the developed films, we demonstrate by dynamometer measurements the higher degree of mechanical work performed by the aligned MIL-88A@polymer films with the preserved anisotropies compared to the unaligned films. The insights provided by this work into anisotropic properties displayed by aligned MIL-88A@polymer films promise to translate crystal performance benefits measured in laboratories into real-world applications. We anticipate that our work is a starting point to utilize the full potential of anisotropic properties of MOFs.

To increase the red blood cell (RBC) cryopreservation efficiency by metal-organic frameworks (MOFs), a dimensional reduction approach has been proposed. Namely, 3D MOF nanoparticles are progressively reduced to 2D ultra-thin metal-organic layers (MOLs). We found that 2D MOLs are beneficial for enhanced interactions of the interfacial hydrogen-bonded water network and increased utilization of inner ordered structures, due to the higher surface-to-volume ratio. Specifically, a series of hafnium (Hf)-based 2D MOLs with different thicknesses (monolayer to stacked multilayers) and densities of hydrogen bonding sites have been synthesized. Both ice recrystallization inhibition activity (IRI) and RBCs cryopreservation assay confirm the pronounced better IRI activity and excellent cell recovery efficiency (up to approximate to 63% at a very low concentration of 0.7 mgmL(-1)) of thin-layered Hf-MOLs compared to their 3D counterparts, thereby verifying the dimensional reduction strategy to improved cryoprotectant behaviors.

Hyperuricemia, caused by an imbalance between the rates of production and excretion of uric acid (UA), may greatly increase the mortality rates in patients with cardiovascular and cerebrovascular diseases. Herein, for fast-acting and long-lasting hyperuricemia treatment, armored red blood cell (RBC) biohybrids, integrated RBCs with proximal, cascaded-enzymes of urate oxidase (UOX) and catalase (CAT) encapsulated within ZIF-8 framework-based nanoparticles, have been fabricated based on a super-assembly approach. Each component is crucial for hyperuricemia treatment: 1) RBCs significantly increase the circulation time of nanoparticles; 2) ZIF-8 nanoparticles-based superstructure greatly enhances RBCs resistance against external stressors while preserving native RBC properties (such as oxygen carrying capability); 3) the ZIF-8 scaffold protects the encapsulated enzymes from enzymatic degradation; 4) no physical barrier exists for urate diffusion, and thus allow fast degradation of UA in blood and neutralizes the toxic by-product H2 O2 . In vivo results demonstrate that the biohybrids can effectively normalize the UA level of an acute hyperuricemia mouse model within 2 h and possess a longer elimination half-life (49.7 ± 4.9 h). They anticipate that their simple and general method that combines functional nanomaterials with living cell carriers will be a starting point for the development of innovative drug delivery systems.

Hydrogen-bonded organic frameworks (HOFs) possessing high crystallinity, simple synthetic procedure and easy regeneration provide high efficiency as multifunctional systems, including applications as proton conductors. Porphyrinylphosphonates having acidic moieties, which can form multiple hydrogen bonds, together with tunable physical-chemical properties of a macrocycle may significantly improve the proton conductivity of such materials. Herein, the synthesis, characterization and proton-conducting properties of a novel anionic HOF based on a new complex of palladium(II) with meso-tetrakis(4-(phosphonatophenyl))porphyrin, HOF-IPCE-1Pd, are reported. Directed structural transformation of the framework by the exchange of dimethylammonium counterions for ammonium cations along with the absorption of ammonia and water molecules led to the formation of a more hydrolytically stable structure of HOF-IPCE-1Pd-NH3, demonstrating the proton conductivity of 1.27 × 10-3 S cm-1 at 85 °C and 85% RH, which is one of the highest among all known HOFs based on porphyrins. It is noteworthy that the reversible absorbance of water/ammonia molecules preserves the crystal structure of HOF-IPCE-1Pd-NH3.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

A novel ionogenic water-soluble zinc complex with n-extended ligand - tetraquinoxalinoporphyrazine bearing eight benzoate groups - ZnQPz(COONa)8 was synthesized by template condensation of a new building block, dipentyl 4,4'-(6,7-dicyanoquinoxalin-2,3-diyl)dibenzoate followed by alkaline hydrolysis of ester groups. The photophysical properties of the complex were studied and a significant bathochromic shift of the Q-band by 100 nm was observed as compared to conventional phthalocyanine complexes. However, in contrast to other NIR-absorbing n-extended derivatives with similar optical properties, ZnQPz(COONa)8 showed a high degree of photostability - its photobleaching rate in DMSO was about 3 times lower than that of the zinc tetra-15-crown-5-naphthalocyanate Zn[(15C5)4Nc]. The improved photostability together with the ability to generate singlet oxygen (CYRILLIC CAPITAL LETTER EF Delta = 0.65 in aqueous DMSO) and absorb light in the near infrared region makes quinoxaline-porphyrazine a good candidate for use in photodynamic therapy.

The coordination-driven design and synthesis of new stable supramolecular cluster-porphyrin (CP) hybrids based on an A2-type ruthenium porphyrin 5,15-bis[(p-tolyl)porphyrinato(2-)]ruthenium(carbonyl)(aqua) [RuDTolP(CO)H2O] and an octahedral molybdenum(II) iodide cluster with six terminal isonicotinate ligands (Bu4N)2[{Mo6I8}(OOC-C5H4N)6] (PyMoC) are reported. The stepwise supramolecular assembly of the PyMoC "superoctahedron" with RuDTolP(CO)H2O has been studied by 1H NMR and 2D 1H-1H COSY, 1H-15N HMBC and DOSY techniques, as well as by UV-vis spectroscopy and HR-ESI mass spectrometry. The formation of discrete cluster-porphyrin CPn adducts with different numbers of coordinated porphyrins (n = 1-6), including the geometrical isomers of CP2, CP3 and CP4, has been observed. Using a double equivalent amount of RuDTolP(CO)H2O relative to the cluster (C : P ratio 1 : 12) affords a mixture of CP5 and CP6 species in solution, while only the CP6 complex is crystallized from this system. Fine tuning of crystallization conditions leads to the formation of a more complex architecture CP6+2, where the CP6 assembly incorporates two additional porphyrin molecules bound to the cluster core by hydrogen bonds. Thus, the coordination-based supramolecular approach provides new stable cluster-multiporphyrin 3D arrays based on two types of photosensitizers, which can be promising for the design of photoactive materials.

The paper presents the results of the synthesis, a detailed kinetics study, and an investigation of the biological activity of silver nanoparticles (AgNPs) in aqueous solutions of N-reacetylated oligochitosan hydrochloride. UV–visible spectrophotometry and dynamic light scattering were employed to control silver ion reduction. The process was observed to follow a pseudo-first-order law. Transmission and scanning electron microscopy demonstrated that AgNPs ranging in size from 10 to 25 nm formed aggregates measuring 60 to 90 nm, with the aggregate surface coated by a 2–4 nm chitosan shell. X-ray microanalysis and powder X-ray diffractometry were used to study the phase composition, identifying two crystalline phases, nanocrystalline silver and AgCl, present in the dispersions. The antibacterial effect was assessed using the serial dilution method for dispersions with varying degrees of Ag+ conversion. Nanodispersions exhibited significant activity against Escherichia coli, Pseudomonas aeruginosa, Bacillus cereus, and Staphylococcus aureus. Interestingly, the activity did not appear to be heavily influenced by the presence of the AgCl phase or the concentration of Ag+ ions. These synthesized dispersions hold promise for the development of materials tailored for biomedical applications.

The unique properties of porous metal-organic frameworks are responsible for the increasing research interest in the design and synthesis of this type of materials. A general strategy towards targeted design of metal-organic frameworks possessing desired properties is a choice of optimal linkers, which are usually represented by polytopic organic ligands. Porphyrins are promising building blocks for such frameworks due to their tunable physicochemical properties and wide possibilities of macrocycle modification. The achievements of the last decade in the development of synthetic approaches to porphyrin functionalization have promoted fast progress of tetrapyrrole chemistry as the basis of metal-organic frameworks. This review gives analysis of the current literature devoted to the synthesis of porphyrin-based metal-organic frameworks and the prospects for their application in modern materials science. The bibliography includes 262 references.