Mechanochemical Procedures Research Articles

Revisiting the Potential of Group VI Inorganic Precatalysts for the Ethenolysis of Fatty Acids through a Mechanochemical Approach.

The utilization of biobased feedstocks to prepare useful compounds is a pivotal trend in current chemical research. Among a varied portfolio of naturally available starting materials, fatty acids are abundant, versatile substrates with multiple applications. In this context, the ethenolysis of unsaturated fatty acid esters such as methyl oleate is an atom-economical way to prepare functional C10 olefins with a biobased footprint. Despite the existence of a variety of metathesis catalysts for the latter process, there is a lack of readily available, efficient, and inexpensive catalytic systems based on earth-abundant metals (Mo, W) whose preparation does not require sophisticated syntheses and manipulations. Here, a systematic exploration of homogeneous and heterogeneous inorganic Mo, W (oxy)halides shows that MoOCl4, while inactive as a homogeneous species, forms active and selective silica-supported ethenolysis precatalysts able to reach equilibrium conversion of methyl oleate within a few minutes upon activation with SnMe4. Such heterogeneous MoOCl4-based precatalysts were easily accessed through mechanochemical solvent-free procedures and found to contain, upon characterization by elemental analysis and Raman spectroscopy, isolated (≡SiO)Mo(=O)Cl3 units or polymeric silica-supported [-O(≡SiO)nMoCl4-nO-]m (n = 1, 2) complexes depending on the molybdenum loading. The former isolated species exhibited a higher catalytic performance. The developed heterogeneous precatalysts could be applied to the ethenolysis of various substrates, including polyunsaturated fatty acid esters and industrial fatty acid methyl ester (FAME) mixtures from palm oil transesterification.

Structural Features and Optical Properties of All-Inorganic Zero-Dimensional Halides Cs4PbBr6-xIx Obtained by Mechanochemistry.

Despite the great success of hybrid CH3NH3PbI3 perovskite in photovoltaics, ascribed to its excellent optical absorption properties, its instability toward moisture is still an insurmountable drawback. All-inorganic perovskites are much less sensitive to humidity and have potential interest for solar cell applications. Alternative strategies have been developed to design novel materials with appealing properties, which include different topologies for the octahedral arrangements from three-dimensional (3D, e.g., CsPbBr3 perovskite) or two-dimensional (2D, e.g., CsPb2Br5) to zero-dimensional (0D, i.e., without connection between octahedra), as the case of Cs4PbX6 (X = Br, I) halides. The crystal structure of these materials is complex, and their thermal evolution is unexplored. In this work, we describe the synthesis of Cs4PbBr6-xIx (x = 0, 2, 4, 6) halides by mechanochemical procedures with green credentials; these specimens display excellent crystallinity enabling a detailed structural investigation from synchrotron X-ray powder diffraction (SXRD) data, essential to revisit some features in the temperature range of 90-298 K. In all this regime, the structure is defined in the trigonal R3̅c space group (#167). The presence of Cs and X vacancies suggests some ionic mobility into the crystal structure of these 0D halides. Bond valence maps (BVMs) are useful in determining isovalent surfaces for both Cs4PbBr6 and Cs4PbI6 phases, unveiling the likely ionic pathways for cesium and bromide ions and showing a full 3D connection in the bromide phase, in contrast to the iodide one. On the other hand, the evolution of the anisotropic displacement parameters is useful to evaluate the Debye temperatures, confirming that Cs atoms have more freedom to move, while Pb is more confined at its site, likely due to a higher covalency degree in Pb-X bonds than that in Cs-X bonds. Diffuse reflectance ultraviolet-visible (UV-vis) spectroscopy shows that the optical band gap can be tuned depending on iodine content (x) in the range of 3.6-3.06 eV. From density functional theory (DFT) simulations, the general trend of reducing the band gap when Br is replaced by I is well reproduced.

The Effect of Hydrothermal, Microwave, and Mechanochemical Treatments of Tin Phosphate on Sorption of Some Cations

The samples of precipitated tin (IV) phosphate, modified using hydrothermal, microwave, and mechanochemical procedures, were studied in the process of Cs(I), Sr(II), and U(VI) ion sorption. The initial and modified samples were investigated before and after sorption using XRD, XRF, FTIR, and nitrogen adsorption–desorption. It was found that the modification procedures transformed the micro-mesoporous structure of the initial sample into a meso–macroporous structure. As a result, the sorption capacity in relation to all ions increases several times. This indicates the determining role of the porous structure, primary content, and mesopore size on the sorption activity of tin phosphate. The samples, treated in the form of a wet gel, which is a novel procedure, showed the maximum sorption indicators. The sorption of all the tested ions is described by the Langmuir isotherm.

Low-Dimensional Magnetism in Multivariate Copper/Zinc MOF-74 Materials Formed via Different Mechanochemical Methods.

MOF-74 is an archetypal magnetic metal-organic framework (MOF) family, with metal nodes bridged by 2,5-dioxido-1,4-benzenedicarboxylic acid (H4dobdc) and arranged into one of the simplest representations of the 1D Ising magnetic model. Recently, a novel mechano-synthetic approach opened a pathway toward a series of bimetallic multivariate (1:1) M1M2-MOF-74 materials, with the uniform distribution of metal cations in the oxometallic chains, offering a unique opportunity to investigate low-dimensional magnetism in these heterometallic MOFs. We explore here how different mechanochemical procedures affect the interaction between the metal nodes of the model system of three multivariate copper(II)/zinc(II)-MOF-74 materials, two of which were obtained through a template-controlled procedure, and the third one was obtained by recently developed mechanical MOF-alloying combined with subsequent accelerated aging. While the three Cu/Zn-MOF-74 products have almost identical powder X-ray diffraction (PXRD) diffractograms and Fourier transform infrared spectra, they differ significantly in their magnetic properties, as revealed through detailed magnetization and X-band and multifrequency high-field electron spin resonance measurements. The magnetic results of the three multivariate Cu/Zn-MOF-74s were compared to the properties of the monometallic Cu-MOF-74, which shows antiferromagnetic intrachain and weaker ferromagnetic interchain interactions. Energy-dispersive X-ray spectroscopy/scanning electron microscopy and solid-state nuclear magnetic resonance spectroscopy helped rationalize the observed differences in magnetization, and in situ synchrotron PXRD monitoring of template-controlled MOF formation revealed different reaction pathways when using the zinc or copper intermediates, involving even the fleeting occurrence of a rare MOF-74 polymorph.

Detailed Structural Features of the Perovskite-Related Halide RbPbI3 for Solar Cell Applications.

All-inorganic lead halide perovskites like CsPbBr3, CsPbI3, or RbPbI3 are good replacements for the classical hybrid organic–inorganic perovskites like CH3NH3PbI3, susceptible to fast degradation in the presence of humid air. They also exhibit outstanding light absorption properties suitable for solar energy applications. Here, we describe the synthesis of RbPbI3 by mechanochemical procedures with green credentials, avoiding toxic or expensive organic solvents; this specimen exhibits excellent crystallinity. We report neutron powder diffraction data, essential to revisit some subtle structural features around room temperature (200–400 K). In all these regimes, the orthorhombic Pnma crystal structure is characterized by the presence along the b direction of the crystal of double rows of edge-sharing PbI6 octahedra. The lone electron pairs of Pb2+ ions have a strong stereochemical effect on the PbI6 octahedral distortion. The relative covalency of Rb–I versus Pb–I bonds shows that the Pb–I-related motions are more rigid than Rb–I-related vibrations, as seen in the Debye temperatures from the evolution of the anisotropic displacements. The optical gap, measured by diffuse reflectance UV–vis spectroscopy, is ∼2.51 eV and agrees well with abinitio calculations. The thermoelectric Seebeck coefficient is 3 orders of magnitude larger than that of other halide perovskites, with a value of ∼117,000 μV·K–1 at 460 K.

Mechanochemistry: A Green Approach in the Preparation of Pharmaceutical Cocrystals.

Mechanochemistry is considered an alternative attractive greener approach to prepare diverse molecular compounds and has become an important synthetic tool in different fields (e.g., physics, chemistry, and material science) since is considered an ecofriendly procedure that can be carried out under solvent free conditions or in the presence of minimal quantities of solvent (catalytic amounts). Being able to substitute, in many cases, classical solution reactions often requiring significant amounts of solvents. These sustainable methods have had an enormous impact on a great variety of chemistry fields, including catalysis, organic synthesis, metal complexes formation, preparation of multicomponent pharmaceutical solid forms, etc. In this sense, we are interested in highlighting the advantages of mechanochemical methods on the obtaining of pharmaceutical cocrystals. Hence, in this review, we describe and discuss the relevance of mechanochemical procedures in the formation of multicomponent solid forms focusing on pharmaceutical cocrystals. Additionally, at the end of this paper, we collect a chronological survey of the most representative scientific papers reporting the mechanochemical synthesis of cocrystals.

Referral patterns for catheter-directed thrombolysis for iliofemoral deep venous thrombosis.

Post thrombotic syndrome (PTS) is a serious complication of deep venous thromboses (DVTs). PTS occurs more frequently and severely following iliofemoral DVT compared to distal DVTs. Catheter directed thrombolysis (CDT) of iliofemoral DVTs may reduce PTS incidence and severity.We aimed to determine the rate of iliofemoral DVT within our institution, their subsequent management, and compliance with NICE guidelines. Retrospective review of all DVTs diagnosed over a 3-year period was conducted. Cases of iliofemoral DVT were identified using ICD-10 codes from patient notes, and radiology reports of Duplex scans. Further details were retrieved, such as patient demographics and referrals to vascular services. NICE guidance was applied to determine if patients would have been suitable for CDT. A survey was sent to clinicians within medicine to identify awareness of CDT and local guidelines for iliofemoral DVT management. 225 patients with lower limb DVTs were identified. Of these, 96 were radiographically confirmed as iliofemoral DVTs. The median age was 77. 67.7% of iliofemoral DVTs affected the left leg. Right leg DVTs made up 30.2% and 2.1% were bilateral DVTs. Of the 96 iliofemoral DVTs, 21 were deemed eligible for CDT. Only 3 patients (14.3%) were referred to vascular services, and 3 received thrombolysis.From our survey, 95.5% of respondents suggested anticoagulation alone as management for iliofemoral DVT. Only one respondent recommended referral to vascular services. There was a knowledge deficiency regarding venous anatomy, including superficial versus deep veins. CDT and other mechanochemical procedures have been shown to improve outcomes of patients post-iliofemoral DVT, however a lack of awareness regarding CDT as a management option results in under-referral to vascular services. We suggest closer relations between vascular services and their "tributary" DVT clinics, development of guidelines and robust care pathways in the management of iliofemoral DVT.

The investigation of reinforcement properties of nano-CaCO3 synthesized from Achatina fulica snail shell through mechanochemical methods on epoxy nanocomposites

The current study investigates the reinforcement properties of novel nano-calcium carbonate (nano-CaCO3) synthesized from Achatina fulica snail shell. The shell was wet-milled to nanoparticle sizes using mechanochemical procedures. Epoxy nanocomposites prepared with nanofiller content ranges of 1–7 wt.% were fabricated using a conventional resin casting method. Thermal stability and degradation with mechanical properties such as tensile strength, impact strength, and the hardness properties of prepared nanocomposites were determined. It was observed that the reinforcement by the synthesized nano-CaCO3 improved the thermal stability and mechanical properties of neat epoxy irrespective of the filler content. Significantly, the inclusion of 1 w.% Achatina fulica snail shell nanoparticles increased the neat epoxy tensile strength by 75%, stiffness by over 25%, impact strength by 25%, and hardness 35%. These improved properties indicate that nano-CaCO3 synthesized from A. fulica snail shell possesses suitable reinforcement properties that can be used for nanocomposite fabrication.

Cost-efficient and user-friendly 17O/18O labeling procedures of fatty acids using mechanochemistry.

Two mechanochemical procedures for 17O/18O-isotope labeling of fatty acids are reported: a carboxylic acid activation/hydrolysis approach and a saponification approach. The latter route allowed first-time enrichment of important polyunsaturated fatty acids (PUFAs) including docosahexaenoic acid (DHA). Overall, a total of 9 pure labeled products were isolated in high yields (≥80%) and with high enrichment levels (≥37% average labeling of C=O and C-OH carboxylic oxygen atoms), under mild conditions, and in short time (<half day).

Tunable Fulleretic Sodalite MOFs: Highly Efficient and Controllable Entrapment of C60 Fullerene via Mechanochemistry

Encapsulation and confinement of fullerene guests in metal-organic frameworks (MOFs) lead to a novel class of crystalline fulleretic materials with unique physicochemical properties and a broad field of potential applications. The control over the amount of target guests confined in the MOF structure remains a significant challenge, which is particularly pronounced in the confinement of hardly accessible fullerene derivatives. The main strategies used in constructing fulleretic composites are limited by the solubility of components used and solvent versus guest competition for inhabitation of the framework voids. As mechanochemical procedures often overcome these issues, we developed here solvent-free processing by ball milling to gain control over the encapsulation of bulky and rigid C60-fullerene into a sodalite MOF with large cages and narrow cage-apertures. A rapid, green, efficient, and stoichiometry-controlled mechanochemical processing afforded four model C60@zeolitic-imidazolate framework 8 (ZIF-8) crystalline materials containing target 15, 30, 60, and 100 mol % of fullerene entrapped in the accessible cages of the model sodalite zeolitic-imidazolate framework 8 (ZIF-8), in stark contrast to the solution-based strategies that resulted in almost no loading. Varying the fullerene content affects the framework’s vibrational properties, color and luminescence of the composites, and the electron-dose radiation stability. The computational and spectroscopic studies show that the fullerene is accommodated in the cage’s center and that the cage-to-cage transport is a hardly feasible and energetically unfavored process. However, the fast release of C60 molecules from ZIF-8 can be effectively controlled by the pH. The entrapment of fullerene molecules in ZIF-8 resulted in their effective isolation even in higher loadings, paving the way to other tunable porous fulleretics containing single-molecule magnets or nanoprobes available on low scales.

Ribose-borate esters as potential components for prebiological evolution

Ribose-borate esters or Borate-Bound Species (BBS) with ribose were studied in aqueous solution by NMR and infrared (ATR) spectroscopies, as well as by DSC, PXRD and infrared spectroscopy (DRIFT) after mixing d-ribose and borate by mechanochemical procedures. NMR titrations of solutions of d-ribose by borate and borate by d-ribose were carried out, followed by 1H and 11B NMR analysis, revealing that an excess of d-ribose (relative to borate) leads to the formation of diesters and monoesters; both types of esters are stable under the studied conditions. The occurrence of furanose and the number of chemical bonds to the boron atom were confirmed by infrared spectroscopy. Interaction of Na+ with BBS revealing an ionic character was clarified by 23Na NMR spectroscopy. The samples obtained by mechanochemical procedures were amorphous, and with excess of borate present, increase their thermal stability at least up to 140 °C. These results expand the conditions of BBS as reagents in prebiotic reactions. Additionally, BBS exhibit uncommon chemical characteristics.

Synthesis and Crystal Structure of Solvated Complexes of Copper(II) with Serine and Phenanthroline and Their Solid-State-to-Solid-State Transformation into One Stable Solvate

Reactions of copper(II) sulfate with 1,10-phenanthroline, l-serine, and a base were investigated under different solution-based and mechanochemical synthetic procedures. Six complexes with serine were obtained: [Cu(l-ser)(H2O)(phen)]2SO4·xH2O (x = 4, 6, or 10; 1·4H2O, 1·6H2O, and 1·10H2O), [Cu(l-ser)(H2O)(phen)][Cu(l-ser)(CH3OH)(phen)]SO4·3H2O·CH3OH (1·2·3H2O·CH3OH), [Cu(l-ser)(CH3OH)(phen)]2SO4·xCH3OH (x = 2 or 2.5; 2·2CH3OH and 2·2.5CH3OH), and two without serine: [Cu(SO4)(phen)2]·xH2O (x = 4.5 or 6.75; 3·4.5H2O and 3·6.75H2O) (phen = 1,10-phenanthroline, l-ser = l-serinato). The X-ray crystal structure analysis of serine-containing complexes revealed extensive hydrogen bonding and π-interactions that link complex cations, sulfate anions, and solvent molecules into three-dimensional architectures. Most of the water/methanol solvent molecules in these porous compounds are found in channels, some in pockets connected to channels, and can be exchanged in vapors of the other solvent. Along with the solvent ...

Solid-state mechanochemical ω-functionalization of poly(ethylene glycol).

Poly(ethylene glycol) (PEG) is a linear polymer with a wide range of applications in chemical manufacturing, drug development and nanotechnology. PEG derivatives are being increasingly used to covalently modify small molecule and peptide drugs, as well as bioactive nanomaterials in order to improve solubility in biological serum, reduce immunogenicity, and enhance pharmacokinetic profiles. Herein we present the development of mechanochemical procedures for PEG functionalization without the need for bulk solvents, offering a cleaner and more sustainable alternative to existing solution-based PEG procedures. The herein presented mechanochemical procedures enable rapid and solvent-free derivatization of PEG with tosyl, bromide, thiol, carboxylic acid or amine functionalities in good to quantitative yields and with no polymer chain oligomerization, proving the versatility of the method.

Strain-induced skeletal rearrangement of a polycyclic aromatic hydrocarbon on a copper surface

Controlling the structural deformation of organic molecules can drive unique reactions that cannot be induced only by thermal, optical or electrochemical procedures. However, in conventional organic synthesis, including mechanochemical procedures, it is difficult to control skeletal rearrangement in polycyclic aromatic hydrocarbons (PAHs). Here, we demonstrate a reaction scheme for the skeletal rearrangement of PAHs on a metal surface using high-resolution noncontact atomic force microscopy. By a combination of organic synthesis and on-surface cyclodehydrogenation, we produce a well-designed PAH—diazuleno[1,2,3-cd:1′,2′,3′-fg]pyrene—adsorbed flatly onto Cu(001), in which two azuleno moieties are highly strained by their mutual proximity. This local strain drives the rearrangement of one of the azuleno moieties into a fulvaleno moiety, which has never been reported so far. Our proposed thermally driven, strain-induced synthesis on surfaces will pave the way for the production of a new class of nanocarbon materials that conventional synthetic techniques cannot attain.

Hydrothermal and mechanochemical synthesis of crystalline CaCO3

Mechanochemical and microwave-assisted hydrothermal (MicroWave Treatment [MWT]) procedures were applied to prepare crystalline CaCO3. Mechanochemical process was carried out at different speeds of rotation (500 or 850 rpm/min), different duration times (30 or 60 min) and in the aqueous suspensions or in dry state. MWT synthesis was conducted in a saturated water vapour or under the layer of water. The crystalline and porous structures of the prepared samples as well as their morphology were investigated using N2 adsorption, X-ray diffraction and scanning electron microscopy methods. As a result, the calcium carbonate samples in the form of calcite were obtained. The materials prepared by the mechanochemical route performed in the aqueous suspension are characterized by smaller crystallite sizes as compared to those obtained without the addition of water. The samples obtained hydrothermally have the largest size of crystallites. Powders prepared by energetical milling possess higher values of specific surface area in relation to the parameter for those synthesized hydrothermally. In the process of hydrothermal treatment, macroporous structure of the prepared materials is created. With the increasing specific surface area of the sample, the size of the crystallites decreased.

Tailoring the properties of a zero-valent iron-based composite by mechanochemistry for nitrophenols degradation in wastewaters

ABSTRACTZero-valent iron (ZVI) is a valuable material for environmental remediation, because of its safeness, large availability, and inexpensiveness. Moreover, its reactivity can be improved by addition of (nano-) particles of other elements such as noble metals. However, common preparation methods for this kind of iron-based composites involve wet precipitation of noble metal salt precursors, so they are often expensive and not green. Mechanochemical procedures can provide a solvent-free alternative, even at a large scale. The present study demonstrates that it is possible to tailor functional properties of ZVI-based materials, utilizing high-energy ball milling. All main preparation parameters are investigated and discussed. Specifically, a copper-carbon-iron ternary composite was prepared for fast degradation of 4-nitrophenol (utilized as model pollutant) to 4-aminophenol and other phenolic compounds. Copper and carbon are purposely chosen to insert specific properties to the composite: Copper acts as efficient nano-cathode that enhances electron transfer from iron to 4-nitrophenol, while carbon protects the iron surface from fast oxidation in open air. In this way, the reactive material can rapidly reduce high concentration of nitrophenols in water, it does not require acid washing to be activated, and can be stored in open air for one week without any significant activity loss.

Multi-step and multi-component organometallic synthesis in one pot using orthogonal mechanochemical reactions

We demonstrate that the mechanochemical strategies for oxidative addition and ligand substitution on organometallic centers can be mutually orthogonal, permitting the rational design of multi-component mechanochemical reaction procedures for assembling complex or solution-sensitive organometallic species from three, four or even five components in one pot. The herein established synthetic procedures represent a new level of complexity in mechanochemical reactions by milling and are the first to combine redox and ligand substitution reactions into mechanochemical strategies for either one-pot sequential (“telescoping”) or one-pot multi-component syntheses. This ability to combine mechanochemical transformations has enabled the solvent-free, room-temperature syntheses of relatively complex organometallics directly for simple zerovalent metal carbonyls as the simplest precursors. In particular, we demonstrate the efficiency of mechanochemical oxidative addition by targeting selected pentacarbonyl halides (fluoride, chloride, bromide, iodide) of rhenium(I) and manganese(I), and illustrate the potential of multi-step organometallic mechanochemistry in the syntheses of selected fac-tricarbonyl complexes of these metals.

Assembly of 3D Coordination Polymers from 2D Sheets by [2+2] Cycloaddition Reaction

The synthesis of three 2D interdigitated Zn(II) coordination polymers (CPs), by using three monotopic ligands containing C=C bonds, is reported. Among these, two CPs with 4spy (4-styryl pyridine) and 2F-4spy (a 2'-fluoro derivative of 4spy) ligands showed quantitative formation of cyclobutane rings, thus demonstrating a unique synthetic procedure to synthesize metal-organic frameworks (MOFs) by using this photochemical reaction. Interestingly, these compounds can also be synthesized by mechanochemical grinding procedures by using Zn(OAc)2. In contrast, Zn(NO3)2 did not yield the required product, unlike in the solution route. In addition, compounds with 4vpy (4-vinylpyridine), 4spy and 2F-4spy ligands created different units in the CPs; 4vpy and 2F-4spy furnished paddle wheel units, whereas 4spy yielded tetrahedral Zn(II) repeating units. Furthermore, the change in coordination geometry manifests in the photoluminescence properties, attributed to the difference in charge-transfer and ligand-centered fluorescent phenomenon.

Click Mechanochemistry: Quantitative Synthesis of “Ready to Use” Chiral Organocatalysts by Efficient Two‐Fold Thiourea Coupling to Vicinal Diamines

Mechanochemical methods of neat grinding and liquid-assisted grinding have been applied to the synthesis of mono- and bis(thiourea)s by using the click coupling of aromatic and aliphatic diamines with aromatic isothiocyanates. The ability to modify the reaction conditions allowed the optimization of each reaction, leading to the quantitative formation of chiral bis(thiourea)s with known uses as organocatalysts or anion sensors. Quantitative reaction yields, combined with the fact that mechanochemical reaction conditions avoid the use of bulk solvents, enabled solution-based purification methods (such as chromatography or recrystallization) to be completely avoided. Importantly, by using selected model reactions, we also show that the described mechanochemical reaction procedures can be readily scaled up to at least the one-gram scale. In that way, mechanochemical synthesis provides a facile method to fully transform valuable enantiomerically pure reagents into useful products that can immediately be applied in their designed purpose. This was demonstrated by using some of the mechanochemically prepared reagents as organocatalysts in a model Morita-Baylis-Hillman reaction and as cyanide ion sensors in organic solvents. The use of electronically and sterically hindered ortho-phenylenediamine revealed that mechanochemical reaction conditions can be readily optimized to form either the 1:1 or the 1:2 click-coupling product, demonstrating that reaction stoichiometry can be more efficiently controlled under these conditions than in solution-based syntheses. In this way, it was shown that excellent stoichiometric control by mechanochemistry, previously established for mechanochemical syntheses of cocrystals and coordination polymers, can also be achieved in the context of covalent-bond formation.

Mechanochemistry: A review of surface reactions and environmental applications

Mechanochemistry is the study of physico-chemical transformations generated by mechanical force. This force may break down crystals, thus exposing fresh, active surfaces and enhance the mass transfer required for reaction partners in the solid state to make the contact required for initiating a chemical reaction. Application of mechanical force may facilitate sorption-induced steric enhancement of transformations catalyzed by ions of transition metals (e.g., cations of such metals serving as counter ions in exchange complexes of clays). The formation of mixed Cu–Na–montmorillonite from Na–montmorillonite ground with CuCl2 in the presence of imazaquin and the resultant breakdown of imazaquin is one example of this phenomenon. Reported mechanochemical reactions which involve minerals, include redox reactions, polymerization and polymer rearrangements, recrystallization and dehydration. The more widespread methods for removing organic contaminants from soils are based on biological degradation. Biological processes, however, have certain shortcomings such as the substantial time they require, or the significant concentrations of harmful residues that are left in the soil. Alternative soil remediation schemes are, therefore, needed and mechanochemical procedures may be part of such innovative cleanup protocols. Mechanochemistry can be applied at the field scale and mechanochemical techniques were already suggested as a clean and cheap approach to hazardous waste management and destruction. Furthermore, soil tillage is actually a process in which mechanical force is applied to the soil and hence, it may induce a variety of mechanochemical reactions.Clays and metal (especially iron and manganese) oxides catalyze numerous transformations of organic compounds when such compounds are sorbed on the minerals' surfaces. The catalytic efficiency of these minerals is, at least in part, due to their strong acidity, both Bronsted and Lewis, and to the large specific surface area they may possess. Manganese and iron are redox active and their minerals are thus capable of supporting both electron and proton transfer reactions. Since iron oxides are abundant in soils, transformations augmented by these minerals are of considerable environmental importance. In the present review, case studies of mechanochemically induced transformations of pollutants are presented. The breakdown of pesticides (2,4-D, imazaquin and atrazine) and of other organic pollutants such as DCP and PAHs achieved by light grinding for short durations (a few minutes) in a mixture with minerals which are soil components or the derivatives of such components is described. Among the tested minerals, Al– and Cu–montmorillonite, iron oxides and Mn oxides were the most effective heterogeneous catalysts. The effectiveness of the minerals depended strongly on the degraded pollutant and on the conditions (e.g., the moisture content) under which the mechanochemical reaction took place. Although the presence of water often hinders the degradation, in some cases the reverse is true. Na–montmorillonite in the presence of CuCl2 was effective in degrading imazaquin when the mixture was ground wet. This demonstrates a detoxification process applicable to real-world systems which are often wet.