I19-Small Molecule Single Crystal Diffraction
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Paula
Escamilla
,
Marcello
Monteleone
,
Rita Maria
Percoco
,
Teresa F.
Mastropietro
,
Mariagiulia
Longo
,
Elisa
Esposito
,
Alessio
Fuoco
,
Johannes C.
Jansen
,
Rosangela
Elliani
,
Antonio
Tagarelli
,
Jesus
Ferrando-Soria
,
Valeria
Amendola
,
Emilio
Pardo
,
Donatella
Armentano
Diamond Proposal Number(s):
[28808]
Abstract: Heavy metal ions are a common source of water pollution. In this study, two novel membranes with biobased metal–organic frameworks (BioMOFs) embedded in a polyacrylonitrile matrix with tailored porosity were prepared via nonsolvent induced phase separation methods and designed to efficiently adsorb heavy metal ions from oligomineral water. Under optimized preparation conditions, stable membranes with high MOF loading up to 50 wt % and a cocontinuous sponge-like morphology and a high water permeability of 50–60 L m–2 h–1 bar–1 were obtained. The tortuous flow path in combination with a low water flow rate guarantees maximum contact time between the fluid and the MOFs, and thus a high heavy metal capture efficiency in a single pass. The performances of these BioMOF@PAN membranes were investigated in the dynamic regime for the simultaneous removal of Pb2+, Cd2+, and Hg2+ heavy metals from aqueous environments in the presence of common interfering ions. The new composite adsorbing membranes are capable of reducing the concentration of heavy metal pollutants in a single pass and at much higher efficiency than previously reported membranes. The enhanced performance of the mixed matrix membranes is attributed to the presence of multiple recognition sites which densely decorate the BioMOF channels: (i) the thioether groups, deriving from the S-methyl-l-cysteine and (S)-methionine amino acid residues, able to recognize and capture Pb2+ and Hg2+ ions and (ii) the oxygen atoms of the oxamate moieties, which preferentially interact with Cd2+ ions, as revealed by single crystal X-ray diffraction. The flexibility of the pore environments allows these sites to work synergically for the simultaneous capture of different metal ions. The stability of the membranes for a potential regeneration process, a key-factor for the effective feasibility of the process in real life applications, was also evaluated and confirmed less than 1% capacity loss in each cycle.
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Sep 2024
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I19-Small Molecule Single Crystal Diffraction
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Diamond Proposal Number(s):
[28808]
Open Access
Abstract: Mimicking enzymatic processes carried out by natural enzymes, which are highly efficient biocatalysts with key roles in living organisms, attracts much interest but constitutes a synthetic challenge. Biological metal–organic frameworks (bioMOFs) are potential candidates to be enzyme catalysis mimics, as they offer the possibility to combine biometals and biomolecules into open-framework porous structures capable of simulating the catalytic pockets of enzymes. In this work, we first study the catalase activity of a previously reported bioMOF, derived from the amino acid L-serine, with formula {CaIICuII6[(S,S)-serimox]3(OH)2(H2O)} · 39H2O (1) (serimox = bis[(S)-serine]oxalyl diamide), which is indeed capable to mimic catalase enzymes, in charge of preventing cell oxidative damage by decomposing, efficiently, hydrogen peroxide to water and oxygen (2H2O2 → 2 H2O + O2). With these results in hand, we then prepared a new multivariate bioMOF (MTV-bioMOF) that combines two different types of bioligands derived from L-serine and L-histidine amino acids with formula CaIICuII6[(S,S)-serimox]2[(S,S)-hismox]1(OH)2(H2O)}·27H2O (2) (hismox = bis[(S)-histidine]oxalyl diamide ligand). MTV-bioMOF 2 outperforms 1 degrading hydrogen peroxide, confirming the importance of the amino acid residue from the histidine amino acid acting as a nucleophile in the catalase degradation mechanism. Despite displaying a more modest catalytic behavior than other reported MOF composites, in which the catalase enzyme is immobilized inside the MOF, this work represents the first example of a MOF in which an attempt is made to replicate the active center of the catalase enzyme with its constituent elements and is capable of moderate catalytic activity.
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Jul 2024
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I19-Small Molecule Single Crystal Diffraction
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Jordi
Ballesteros-Soberanas
,
Nuria
Martín
,
Matea
Bacic
,
Estefanía
Tiburcio
,
Marta
Mon
,
Juan Carlos
Hernández-Garrido
,
Carlo
Marini
,
Mercedes
Boronat
,
Jesus
Ferrando-Soria
,
Donatella
Armentano
,
Emilio
Pardo
,
Antonio
Leyva-Pérez
Diamond Proposal Number(s):
[28808]
Open Access
Abstract: The removal of acetylene from ethylene streams is key in industry for manufacturing polyethylene. Here we show that a well-defined Pd1–Au1 dimer, anchored to the walls of a metal–organic framework (MOF), catalyses the selective semihydrogenation of acetylene to ethylene with ≥99.99% conversion (≤1 ppm of acetylene) and >90% selectivity in extremely rich ethylene streams (1% acetylene, 89% ethylene, 10% H2, simulated industrial front-end reaction conditions). The reaction proceeds with an apparent activation energy of ∼1 kcal mol–1, working even at 35 °C, and with operational windows (>100 °C) and weight hourly space velocities () within industrial specifications. A combined experimental and computational mechanistic study shows the cooperativity between both atoms, and between atoms and support, to enable the barrierless semihydrogenation of acetylene.
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Mar 2024
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I19-Small Molecule Single Crystal Diffraction
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Diamond Proposal Number(s):
[16033, 18768, 22411, 28808]
Abstract: The chapter is focused on our recent advances in the construction of well-defined metal organic framework (MOF)-driven self-assembly of supramolecular species. The experimental developments, which reside at the connection between supramolecular and reticular chemistry, are summarized. In particular, the discussion is focused on the use of MOFs – an emerging type of porous functional material capable of acting as vessels or as chemical nanoreactors to template the self-assembly of supramolecular coordination compounds (SCCs) or the growth of small aggregations of metal atoms, close to or within the subnanometric regime, so-called metal nanoclusters (MNCs) that are atomically precise nanoclusters, for application in heterogeneous catalysis. All that with a particular focus on how the MOFs' surface engineering, composition manipulation, and support effects can guarantee their stability while tuning their nuclearity/size and catalytic performance. We will show that their crystallographic characterization is still of critical importance in order to shed light on supramolecular host–guest interactions.
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Aug 2023
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I19-Small Molecule Single Crystal Diffraction
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Diamond Proposal Number(s):
[22411]
Abstract: We report the two-step synthesis of a heterobimetallic oxamato-based metal-organic framework (MOF). First, we prepared an oxamato functionalized carbazole-based dinuclear copper(II) complex, K4{Cu2(carbox)2]}·8H2O, where the carbozale linkers exhibited an uncommon substitution pattern, carbox = N,N’-1,6-carbazolebis(oxamate). Then, this building block was used as a metalloligand toward manganese(II) metal ions to assemble a neutral three-dimensional (3 D) MOF with formula [Mn2Cu2(carbox)2(H2O)4]·6CH3OH·2H2O (1) and single-crystal X-ray diffraction determined the structure. The resulting network constitutes one of the few examples of oxamato-based 3 D MOF.
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Sep 2022
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I19-Small Molecule Single Crystal Diffraction
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Diamond Proposal Number(s):
[22411]
Open Access
Abstract: The preparation of novel efficient catalysts─that could be applicable in industrially important chemical processes─has attracted great interest. Small subnanometer metal clusters can exhibit outstanding catalytic capabilities, and thus, research efforts have been devoted, recently, to synthesize novel catalysts bearing such active sites. Here, we report the gram-scale preparation of Ag20 subnanometer clusters within the channels of a highly crystalline three-dimensional anionic metal–organic framework, with the formula [Ag20]@AgI2NaI2{NiII4[CuII2(Me3mpba)2]3}·48H2O [Me3mpba4– = N,N′-2,4,6-trimethyl-1,3-phenylenebis(oxamate)]. The resulting crystalline solid catalyst─fully characterized with the help of single-crystal X-ray diffraction─exhibits high catalytic activity for the catalytic Buchner ring expansion reaction.
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Jul 2022
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I19-Small Molecule Single Crystal Diffraction
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Diamond Proposal Number(s):
[22411]
Open Access
Abstract: Amides and esters are prevalent chemicals in Nature, industry and academic laboratories. Thus, it is not surprising that a plethora of synthetic methods for these compounds has been developed along the years. However, these methods are not 100% atom economical and generally require harsh reagents or reaction conditions. Here we show a “spring–loaded”, 100% atom–efficient amidation and esterification protocol which consists in the ring opening of cyclopropenones with amines or alcohols. Some alkyl amines react spontaneously at room temperature in a variety of solvents and reaction conditions, including water at different pHs, while other alkyl amines, aromatic amines and alcohols react in the presence of catalytic amounts of simple Cu2+ salts or solids. A modular reactivity pattern (alkyl amines >> alkyl alcohols >> phenols >> aromatic amines) enables to design orthogonal and one–pot reactions on well–defined catalytic Multimetal–Organic Frameworks (M–MOFs, M= Cu, Ni, Pd), to easily functionalize the resulting cinnamides and cinnamic esters to more complex molecules. The strong resemblance of the amidation and esterification reaction conditions here reported with the copper–catalyzed azide–alkyne cycloaddition (CuAAC) allows to define this fast, clean and flexible protocol as a click reaction.
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Apr 2022
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I19-Small Molecule Single Crystal Diffraction
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Diamond Proposal Number(s):
[22411]
Abstract: Extremely high electrophilic metal complexes, composed by a metal cation and very electron poor σ–donor ancillary ligands, are expected to be privileged catalysts for oxidation reactions in organic chemistry. However, their low lifetime prevents any use in catalysis. Here we show the synthesis of fluorinated pyridine–Pd 2+ coordinate cages within the channels of an anionic tridimensional metal organic framework (MOF), and their use as efficient metal catalysts for the aerobic oxidation of aliphatic alcohols to carboxylic acids without any additive. Mechanistic studies strongly support that the MOF–stabilized coordination cage with perfluorinated ligands unleashes the full electrophilic potential of Pd 2+ to dehydrogenate primary alcohols, without any base, and also to activate O 2 for the radical oxidation to the aldehyde intermediate. This study opens the door to design catalytic perfluorinated complexes for challenging organic transformations, where an extremely high electrophilic metal site is required.
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Dec 2021
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I19-Small Molecule Single Crystal Diffraction
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Diamond Proposal Number(s):
[18768, 22411]
Open Access
Abstract: Human society is facing—among other environmental threats—an enormous challenge due to human activities. The extensive use of high-tech devices and electronics equipment in the daily life makes, among others, rare-earth elements (REEs) recovery from secondary sources highly required. Here, a novel bioMOF-based single-walled carbon nanotube buckypaper (SWCNTBP) is presented as a new and efficient composite material (BioMOF@SWCNT-BP). The flexible and highly crystalline metal–organic framework (MOF), prepared from the natural amino acid L-threonine, has been homogeneously dispersed within the tangled net of a self-standing SWCNT-BP for lanthanides recovery from water. This MOF-carbon-based membrane exhibits high efficiency, either in static or dynamic regimes, in the recovery of lanthanides from aqueous streams outperforming the state-of-the-art. The capture performances of BPs are successfully improved after incorporation of such MOF featuring hexagonal functional channels decorated with the threonine amino acid residues, pointing toward the accessible void spaces, which boosts the capture properties of the final membrane, providing the adaptable functional environment to interact with lanthanides. This material's preparation presents also a potential for large-scale applications with a potential benefit on natural aquatic ecosystems as well. It is highly demanded because REEs from non-recycled waste materials are potential pollutants for surface waters.
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Aug 2021
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I19-Small Molecule Single Crystal Diffraction
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Diamond Proposal Number(s):
[22411, 25759]
Open Access
Abstract: Circumventing the impact of agrochemicals on aquatic environments has become a necessity for health and ecological reasons. Herein, we report the use of a family of five eco-friendly water-stable isoreticular metal–organic frameworks (MOFs), prepared from amino acids, as adsorbents for the removal of neonicotinoid insecticides (thiamethoxam, clothianidin, imidacloprid, acetamiprid, and thiacloprid) from water. Among them, the three MOFs containing thioether-based residues show remarkable removal efficiency. In particular, the novel multivariate MOF {SrIICuII6[(S,S)-methox]1.5[(S,S)-Mecysmox]1.50(OH)2(H2O)}·36H2O (5), featuring narrow functional channels decorated with both −CH2SCH3 and −CH2CH2SCH3 thioalkyl chains—from l-methionine and l-methylcysteine amino acid-derived ligands, respectively—stands out and exhibits the higher removal efficiency, being capable to capture 100% of acetamiprid and thiacloprid in a single capture step under dynamic solid-phase extraction conditions—less than 30 s. Such unusual combination of outstanding efficiency, high stability in environmental conditions, and low-cost straightforward synthesis in 5 places this material among the most attractive adsorbents reported for the removal of this type of contaminants.
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Jun 2021
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