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The COVID-19 pandemic has claimed millions of lives worldwide, sickened many more, and has resulted in severe socioeconomic consequences. As society returns to normal, understanding the spread and persistence of SARS CoV-2 on commonplace surfaces can help to mitigate future outbreaks of coronaviruses and other pathogens. We hypothesize that such an understanding can be aided by studying the binding and interaction of viral proteins with nonbiological surfaces. Here, we propose a methodology for investigating the adhesion of the SARS CoV-2 spike glycoprotein on common inorganic surfaces such as aluminum, copper, iron, silica, and ceria oxides as well as metallic gold. Quantitative adhesion was obtained from the analysis of measured forces at the nanoscale using an atomic force microscope operated under ambient conditions. Without imposing further constraints on the measurement conditions, our preliminary findings suggest that spike glycoproteins interact with similar adhesion forces across the majority of the metal oxides tested with the exception to gold, for which attraction forces ∼10 times stronger than all other materials studied were observed. Ferritin, which was used as a reference protein, was found to exhibit similar adhesion forces as SARS CoV-2 spike protein. This study results show that glycoprotein adhesion forces for similar ambient humidity, tip shape, and contact surface are nonspecific to the properties of metal oxide surfaces, which are expected to be covered by a thin water film. The findings suggest that under ambient conditions, glycoprotein adhesion to metal oxides is primarily controlled by the water capillary forces, and they depend on the surface tension of the liquid water. We discuss further strategies warranted to decipher the intricate nanoscale forces for improved quantification of the adhesion.

Depolymerization of the addition polymer polystyrene to monomeric styrene is facilitated by mechanochemical processing at room temperature under ambient atmosphere. The reaction occurs in metal-based milling media in concert with scission of macromolecular chains that generates carbon-centered free-radicals detectable by EPR spectroscopy, even though the processing is performed in air.

A new family of heterostructured transition-metal dichalcogenides (TMDCs) with incommensurate (“misfit”) spatial arrangements of well-defined layers was prepared from structurally dissimilar single-phase 2H-MoS2 and 1T-HfS2 materials. The experimentally observed heterostructuring is energetically favorable over the formation of homogeneous multi-principle element dichalcogenides observed in related dichalcogenide systems of Mo, W, and Ta. The resulting three-dimensional (3D) heterostructures show semiconducting behavior with an indirect band gap around 1 eV, agreeing with values predicted from density functional theory. Results of this joint experimental and theoretical study open new avenues for generating unexplored metal-dichalcogenide heteroassemblies with incommensurate structures and tunable physical properties.

Three-dimensional heterostructures are usually created either by assembling two-dimensional building blocks into hierarchical architectures or using stepwise chemical processes that sequentially deposit individual monolayers. Both approaches suffer from a number of issues, including lack of suitable precursors, limited reproducibility, and poor scalability of the preparation protocols. Therefore, development of alternative methods that enable preparation of heterostructured materials is desired. We create heterostructures with incommensurate arrangements of well-defined building blocks using a synthetic approach that comprises mechanical disassembly and simultaneous reordering of layered transition-metal dichalcogenides, MX2, and non-layered monochalcogenides, REX, where M = Ta, Nb, RE = Sm, La, and X = S, Se. We show that the discovered solid-state processes are rooted in stochastic mechanochemical transformations directed by electronic interaction between chemically and structurally dissimilar solids toward atomic-scale ordering, and offer an alternative to conventional heterostructuring. Details of composition–structure–properties relationships in the studied materials are also highlighted., 3D heterostructures offer properties that are inaccessible in bulk single-phase solids, but synthetic approaches are limited. The authors use mechanochemical reshuffling of binary precursors and subsequent annealing to design structurally aligned misfit heterostructures with well-defined atomic arrangements.

Mechanochemical reactions of benzene-1,4-dicarboxylate (BDC2−) and lanthanide carbonates, Ln2(CO3)3·xH2O (Ln = Sm, Eu, Gd, Tb) yield phase pure lanthanide coordination polymers, (Ln0.5Gd0.5)2(1,4-BDC)3(H2O)4 with Ln = Sm, Eu, Tb, which are isostructural with Tb2(1,4-BDC)3(H2O)4 as confirmed by powder X-ray diffraction and vibrational spectroscopy. Upon excitation with UV light all three compounds display strong emissions, characteristic for the respective optically active lanthanide ion, namely, red for Eu3+, green for Tb3+ and orange-red for Sm3+. In case of the Tb3+-containing compound, the energy difference between the triplet energy level of benzene-1,4-dicarboxylate ligand (BDC2−) allows for the most efficient BDC2−–Tb3+ energy transfer. As a consequence, an intense green luminescence with rather long lifetime (0.81 ms) and high quantum yield (22%) is observed after allowed excitation of the BDC2− ligand. The compounds are paramagnetic with no onset of long range magnetic ordering down to liquid He temperatures.

The coupling between structural and magnetic degrees of freedom is crucial for realization of interesting physical phenomena associated with magneto-structural transformations resembling austenite-to-martensite transitions. Despite substantial efforts in design and discovery of materials with strong magnetocaloric effects, a majority of viable candidates are composed of non-earth-abundant and toxic elements, while others involve challenging syntheses and post processing. Guided by advanced density functional theory calculations, we report a new family of compounds, i.e., Mn0.5Fe0.5NiSi1-xAlx [x = 0.045–0.07] exhibiting a giant magnetocaloric effect (MCE) that is tunable near room temperature. Their MCE functionality arises from a distinct magneto-structural transformation between a paramagnetic hexagonal Ni2In-type phase and ferromagnetic orthorhombic TiNiSi-type phase that can be actuated by magnetic field and/or pressure. As the transition is sensitive to external hydrostatic pressure, the same materials should also exhibit a strong barocaloric response in addition to the giant MCE.

Magnetocaloric refrigeration is a solid-state cooling approach that promises high energy efficiency and low environmental impact. It remains uncompetitive with conventional vapor-compression technologies due to lack of high-performing materials that exhibit large magnetocaloric effects in low magnetic fields. Here we report a game-changing enhancement of the magnetocaloric response in a transition-metal-based Ni–Co–Mn–Ti. Mechanically and chemically stable rapidly solidified ribbons exhibit magnetic entropy changes as high as ∼ 27 J⋅kg−1K−1 for a moderate field change of 2 T, comparable to or larger than the best known materials for near-room temperature applications. The ribbons can be easily manufactured in large quantities and the transition temperature can be adjusted by varying Co concentration.

The hydrogen storage properties, and phase compositions of mechanochemically prepared mixtures of xMBH4-SiS2 (x = 2–8), where M = Li or Na, were investigated using gas sorption analysis, powder X-ray diffraction, and infrared and solid-state NMR spectroscopic methods. The 2LiBH4:1SiS2 system forms an amorphous product that releases ca. 4.3 wt % of H2 below 385 °C with a Tonset of 88 °C without detectable diborane emission. The dehydrogenated sample reversibly absorbs 1.5 wt % of H2 at 385 °C under 160 bar pressure. The H2 release from materials with varying LiBH4:SiS2 ratios peaks at 8.2 wt % for the 6LiBH4:1SiS2 composition, with a reversible hydrogen storage capacity of 2.4 wt %. The H2 desorption capacities of the Li-containing systems surpass those of Na-containing systems. Solid-state NMR studies indicate that products of mechanochemical reactions in the LiBH4 SiS2 system consist of one-dimensional chains of edge-sharing SiS4/2 tetrahedra in which the non-bridging S-ends are terminated with Li+, which are further coordinated to the [BH4]− anions. A variety of possible polymorphs in the Li Si S-(BH4) composition space have been identified using first principles and thermodynamic modeling that supports the likelihood of formation of such novel complexes.

A new family of heterostructured transition-metal dichalcogenides (TMDCs) with incommensurate ("misfit") spatial arrangements of well-defined layers was prepared from structurally dissimilar single-phase 2H-MoS

Three metal-organic framework (MOF) compounds, Ln0.5Gd0.5{C6H3(COO)3}; Ln = Eu, Tb, and Dy with a MIL-78 structure, have been synthesized by a solvent-free mechanochemical method from stoichiometric mixtures of benzene 1,3,5-tricarboxylic acid, C6H3(COOH)3, also known as trimesic acid, and the respective lanthanide carbonates, Ln2(CO3)3·xH2O, Ln = Eu, Gd, Tb and Dy. MIL-78 (Ln0.5Gd0.5) shows the characteristic red, green, and yellow luminescence of Eu3+, Tb3+, and Dy3+, respectively. Efficient intramolecular energy transfer from the ligand triplet state to the excited states of Ln3+ ions can be observed. The lifetimes and quantum yields of these compounds are studied and discussed in detail. Among the three compounds, the Tb3+ containing compound shows the longest lifetime and highest quantum yield due to a smaller contribution from non-radiative decay pathways and better matching of the lowest triplet energy level of the benzenetricarboxylate ligand and the resonance level of Tb3+.

Proper coupling between structural and magnetic transitions is critical for the emergence and control of magnetocaloric effects in solids. We examine the influence of minor substitutional doping (replacing Mn by Cr and Al by Sn) and interstitial doping with B on the magnetic, structural, and magnetocaloric properties of recently discovered Mn0.5Fe0.5NiSi0.94Al0.06 alloy exhibiting a giant magnetocaloric effect near room temperature. We demonstrate that magnetocaloric properties of the base compound can be controlled and, in some cases, improved by chemical substitutions. First-principles computations elucidate how small changes in the composition affect properties in this family of compounds and, thus, provide useful guidance for the selection of suitable doping elements for such materials. The magnetic-field-induced entropy change measured for Mn0.5Fe0.5NiSi0.94Al0.06B0.005 is −22 J/kg K near room temperature for the applied magnetic field of 2 T, and it is among the highest known values for this class of materials.

Mechanical milling of benzene 1,3,5-tricarboxylic acid [C 6 H 3 (COOH) 3 ], both with the single and mixed rare earth carbonates [R 2 (CO 3 ) 3 ·xH 2 O; R = Gd, Tb and Dy], leads to the formation of metal-organic frameworks [R{C 6 H 3 (COO) 3 }] that adopt MIL-78 type structure. M ( T ) data of the investigated MOFs do not show any apparent onset of long range magnetic ordering down to 2 K. The M ( H ) data for Gd{C 6 H 3 (COO) 3 }collected at 2 K show deviations from the magnetization behavior expected for non-interacting Gd 3+ ions. For the Gd based MOF the temperature dependence of the isothermal magnetic entropy change (i.e. magnetocaloric effect, Δ S M ) exhibits a monotonous increase with decreasing temperature and at T = 3.5 K it reaches 34.1 J kg −1 K −1 for a field change (Δ H ) of 50 kOe. For the same Δ H the maximum values of Δ S M for R = Tb and Dy are 5.5 J kg −1 K −1 and 8.5 J kg −1 K −1 at 9.5 K and 4.5 K, respectively.

Correction for ‘Depolymerization of polystyrene under ambient conditions’ by Viktor P. Balema et al., New J. Chem., 2021, 45, 2935–2938, DOI: 10.1039/D0NJ05984F.

The efficiency roll-off in blue phosphorescent organic light emitting diodes (OLEDs) using different carbazole compounds as the host is systematically studied. While there is no significant difference in device efficiency, OLEDs using ter-carbazole as the host show a reduction in efficiency roll-off at high luminance. Data from transient photoluminescence and electroluminescence measurements show that the lower triplet–triplet annihilation (TTA) and triplet–polaron quenching (TPQ) rates in devices with the ter-carbazole host compared with other carbazole hosts are the reasons for this reduced efficiency roll-off. It is also found that the host materials with low glass transition temperatures are more susceptible to the efficiency roll-off problem.

Increasing demand for lithium-ion batteries (LIBs) that serve as power source for diverse electronic devices, electrical propulsion systems and other applications, calls for economical and environmentally benign recycling of spent LIBs and recovery of critical elements such as Co and Li from rapidly growing volumes of battery wastes. The presented study explores mechanochemical extraction of Co and Li from lithium cobaltate (LiCoO2), which serves as cathode material in commercial LIBs. Our investigation reveals that solvent-free mechanochemical processing can successfully convert pure, reagent grade LiCoO2 into metallic Co and Li-derivatives that are suitable for the further recovery of Li. We also show that the proposed approach can be successfully applied to reclaiming these critical elements from commercial LIBs. Due to its magnetic nature, metallic Co is easy to separate from non-magnetic components of mechanochemically generated powder mixtures using an appropriate magnetic separation technique, while Li can be reclaimed as Li2CO3 after an additional liquid-phase processing. The recovery rates achieved during our experiments with pure LiCoO2 are ∼90% for Co and ∼70% for Li.

Transition metal dichalcogenides combining multiple principal elements in their structures are synthesized via mechanochemical exfoliation and spontaneous reassembly of binary precursors into 3D-heterostructures that are converted into single-phase layered materials by high-temperature reactive fusion. Physical and chemical events enabling these transformations are summarized in the form of a conceivable reaction mechanism.

The solvent-free reaction between o-vanillin and p-toluidine was investigated using NMR, DSC and XRD analyses. At room temperature, o-vanillin and p-toluidine react in a liquid eutectic formed upon grinding, while below 10 °C the same materials appear to react without the formation of a liquid phase, which most likely remains hidden behind solid reactants and reaction products.

For the first time a metal hydride has been used for the preparation of a metal-organic framework. MIL-78 has been synthesized by the solid-state mechanochemical reaction between yttrium hydride and trimesic acid. The process does not involve solvents and does not generate liquid by-products, thus proving the viability of the solid-state approach to the synthesis of MOFs.

Solid-state nuclear magnetic resonance is used to study the thermal decomposition of lithium tetrahydroaluminate into metallic aluminum, hydrogen and trilithium hexahydroaluminate. Aluminum sites in LiAlH 4 and Li 3 AlH 6 were characterized using static, magic angle spinning (MAS) and multiple-quantum MAS NMR. By applying the in situ NMR method, it has been demonstrated that melting is not a prerequisite for the decomposition of LiAlH 4 . Based on the observed data, a decomposition path has been established that is consistent with the concentrations of observed Al species at various stages of the thermally induced reaction.

Mechanical processing of polycrystalline LiAlH4 in the presence of titanium- and iron-based catalysts induces the transformation of LiAlH4 into Li3AlH6, Al and H2 at room temperature. Several catalysts were tested and it was established that their activity gradually decreases from TiCl4 to Fe in the series TiCl4>Al3Ti≫Al22Fe3Ti8>Al3Fe>Fe. The high catalytic activity of TiCl4 has been attributed to microcrystalline intermetallic Al3Ti, which rapidly forms in situ from TiCl4 and LiAlH4 during mechanical processing and then acts as a heterogeneous dehydrogenation catalyst.

Mechanochemical processing of polycrystalline LiAlH4 revealed good stability of this complex aluminohydride during high-energy ball-milling in a helium atmosphere for up to 35 h. The decomposition of lithium aluminohydride into Li3AlH6, Al and H2 is observed during prolonged mechanochemical treatment for up to 110 h and is most likely associated with the catalytic effect of a vial material, iron, which is introduced into the hydride as a contaminant during mechanical treatment.

Thermodynamically stable Ti 3 Ir with the Cr 3 Si (A15)-type crystal structure can gradually be transformed into a metastable Ti 3 Ir alloy with a bcc crystal structure by high-energy ball-milling for 12.5 h. The long-term ball-milling for up to 112 h, however, is accompanied by a solid-state reaction between Ti 3 Ir and the vial material leading to the formation of a nano-crystalline or amorphous MgZn 2 -type phase with the Ti(Fe 1.85 Ir 0.15 ) stoichiometry and a micro-crystalline thermodynamically stable CsCl-type phase. Both the CsCl- and MgZn 2 -type phases were obtained in the crystalline form after annealing ball-milled Ti 3 Ir. Properties of the A15 Ti 3 Ir alloy changed considerably after ball-milling. The superconducting transition observed in the original A15 alloy at ∼4.3 K no longer exists in the ball-milled material. The electrochemically determined hydrogen storage capacity of the ball-milled alloy also decreases in comparison to the A15 material from 269 to 104 mAh/g. On the contrary, the electrochemical discharge capacity of Ti 3 Ir increases from 45 to 104 mAh/g after ball-milling.

A series of (Sc 1− x Ti x )Ni alloys and their hydrides (Sc 1− x Ti x )NiH y , where x =0, 0.1, 0.3, 0.5, and y =2.9, 2.58, 2.23 and 1.55, have been prepared. The ability to store hydrogen gradually decreases with increasing Ti content in line with the reduction of the unit cell volume from 32.16 A 3 for ScNi to 29.68 A 3 for (Sc 0.5 Ti 0.5 )Ni. The electrochemical discharge capacity, however, varies in a more complex manner with (Sc 0.7 Ti 0.3 )Ni composition displaying the highest value of 231 mAh/g. The discharge capacity losses after 10 electrochemical charge–discharge cycles also vary non-linearly between 46% for (Sc 0.9 Ti 0.1 )Ni and 5% for (Sc 0.5 Ti 0.5 )Ni.

rac-1,2-Bis(phenylchlorophosphino)-1,2-dicarba-closo-dodecaborane(12) (1) reacts with four equivalents of sulfur at 185–190°C in undecane to give the cyclic anhydride of 1,2-bis(phenylthiophosphoryl)-1,2-dicarba-closo-dodecaboranyl(12)-dithiodiphosphinic acid (2). Under comparable conditions,1-phenyl-chlorophosphino-1,2-dicarba-closo-dodecaborane(12) (4) and1-phenylchlorophosphino-2-phenyl-1,2-dicarba-closo-dodecaborane(12) (5) react with sulfur to give 1-phenylchlorothiophosphino-1,2-dicarba-closo-dodecaborane(12) (6) and1-phenylchlorothiophosphino-2-phenyl-1,2-dicarba-closo-dodecaborane(12) (7).Compounds 4–7 were characterized by fn2 fn2 Although the synthesis of 5 was reported earlier [6] , no spectroscopic data were given and the published melting point is 20°C lower than that determined by us for 5. Similarly, differences between our results and those reported previously [6] were also observed for1-phenylchlorothiophos-phine-2-phenyl-1,2-dicarba-closo-dodecaborane(12) (7). H , 31 P, 13 C and 11 B NMR spectroscopy and elemental analysis, and X-ray structure determinations were carried out on 1 and 7.

Bis[2-phenyl-1,2-dicarba-closo-dodecaboran-1-yl(12)]phenylphosphine Viktor P. Balema, Steffen Blaurock, Evamarie Hey-Hawkins* Institut fur Anorganische Chemie der Universitat Leipzig, Talstrasse 35, D-04103 Leipzig, Germany Z. Naturforsch. 53 b, 1273–1276 (1998); received May 20, 1998 Synthesis, Molecular Structure, X-Ray Data, NMR Data, Phosphine Bis[2-phenyl-1,2-dicarba-closo-dodecaboran-1-yl(12)]phenylphosphine (2) was obtained in 91% yield from phenyldichlorophosphine and two equivalents of 1-lithium-2-phenyl-1,2dicarba-closo-dodecaborane(12) in ether and characterized by spectroscopy (P, B, H, C NMR; IR) and by X-ray structure determination.

The complex (R,R\S,S)-[PdCl2{1,2-(PPhCl)2C2B10H10}] (1) was prepared by the reaction of (R,R\S,S)-1,2-(PPhCl)2C2B10H10 with [(COD)PdCl2] (COD = cyclooctadiene) in CH2Cl2 solution and characterized by NMR spectroscopy (31P, 11B, 1H) and X-ray structure determination (space group P−). Due to the crystallographic center of inversion, both enantiomeric isomers (R,R) and (S,S) are present in the unit cell. The Pd atom is coordinated in a square–planar fashion by two chloro ligands and the 1,2-bis(phenylchlorophosphino)-1,2-dicarba-closo-dodecaborane(12).

When a mixture of stereoisomers of rac- and meso-1,2-bis(phenylphosphanyl)-1,2-dicarba-closo-dodecaborane(12) (1a, b; 1a/1b = 3:1) is treated with [Cp2ZrMe2] in boiling toluene for 2 h, the formation of three phosphorus-containing products, namely meso-[Cp2Zr(PPh)3] (3), (PPh)4 (4) and (PPh)5 (5), ratio 2.8:1.1:1.0, was observed by 31P-NMR spectroscopy. In the 11B-NMR spectrum of the reaction mixture, only signals for 1,2-dicarba-closo-dodecaborane(12) were observed. When zirconocene, prepared in situ from [Cp2ZrCl2] and BuLi, was treated with 1a, b at low temperature and then heated to reflux in toluene for 2 h, only formation of 3 and 1,2-dicarba-closo-dodecaborane(12) was observed. The mixture of stereoisomers of 1a, b reacts with CuCl in THF to give rac- and meso-[CuCl(THF){1,2-(PHPh)2C2B10H10}] (7a, b), which is only stable in THF solution and loses THF in vacuo over several hours to yield the insoluble colorless complex [CuCl{1,2-(PHPh)2C2B10H10}]n (8). In THF solution, 7 reacts with PPh3 to give the stable isolable complex [CuCl(PPh3){1,2-(PHPh)2C2B10H10}] (9). No reaction of 1a, b is observed with [Cp′Mo(CO)3]2 (Cp′ = C5H4Me) in boiling THF, while only decomposition occurs in boiling toluene. However, [(NBD)Mo(CO)4] (NBD = norbornadiene) reacts smoothly with 1a in toluene at room temperature to give cis-rac-[Mo(CO)4{1,2-(PHPh)2C2B10H10}] (10). Compounds 7, 9, and 10 were characterized spectroscopically (1H, 31P, 11B, 13C NMR, IR), and an X-ray structure determination was carried out on 10.

The reaction of a diastereomeric mixture of 1,2-bis(phenylchlorophosphino)-1,2-dicarba-closo-dodecaborane(l2) (1) with LiAlH4, followed by hydrolysis with H2O, gives a 4 : 1 mixture of rac- and meso- 1,2-bis(phenylphosphino)-1,2-dicarba-closo-dodecaborane(12) (2a, b) or 1-phenylphosphino-1,2-dicarba- closo-dodecaborane(12) (3), depending on the stoichiometry employed. A mixture of 2a, b reacts with sulfur in undecane at 190°C or without solvent at 105–110°C to give exclusively the cyclic anhydride of 1,2-bis(phenylthiophosphoryl)-1, 2-dicarba-closo-dodecaboranyl(12)-dithiodiphosphinic acid (6). 2, 3 and 6 were characterised spectroscopically (1H, 31P, 11B, 13C NMR, IR, MS) and X-ray structure determinations were carried out on the racemic isomers 2a and 6.

A series of (Sc 1− x Ti x )Ni alloys and their hydrides (Sc 1− x Ti x )NiH y , where x =0, 0.1, 0.3, 0.5, and y =2.9, 2.58, 2.23 and 1.55, have been prepared. The ability to store hydrogen gradually decreases with increasing Ti content in line with the reduction of the unit cell volume from 32.16 A 3 for ScNi to 29.68 A 3 for (Sc 0.5 Ti 0.5 )Ni. The electrochemical discharge capacity, however, varies in a more complex manner with (Sc 0.7 Ti 0.3 )Ni composition displaying the highest value of 231 mAh/g. The discharge capacity losses after 10 electrochemical charge–discharge cycles also vary non-linearly between 46% for (Sc 0.9 Ti 0.1 )Ni and 5% for (Sc 0.5 Ti 0.5 )Ni.

Phosphonium salts have been prepared during high-energy ball-milling of triphenylphosphine with solid organic bromides; the reactions occur at ambient conditions without a solvent; in the case of 2-bromo-2-phenylacetophenone the reaction in a solution usually produces a mixture containing both the C-phosphorylated and O-phosphorylated compounds, while the solvent-free mechanically induced transformation results in the thermodynamically favorable C-phosphorylated product; the occurrence of the observed transformations during mechanical processing of solid reactants is confirmed by the solid-state 31P NMR spectroscopy and X-ray powder diffraction.

We describe the nearly quantitative preparation of phosphorus ylides and the Wittig reaction occurring in the solid sate during high-energy mechanochemical processing. Initial insights into the details of the discovered chemical transformations indicate that high-energy mechanical processing supports the interaction of reacting centers by breaking crystallinity of the reactants and by providing mass transfer without a solvent.

The paper discusses some unresolved issues in the solid state chemistry of alkali metal aluminohydrides (alanates) relevant to high-capacity hydrogen storage. Analysis of experimental data available in chemical and materials science literature suggests a one-step mechanism for the thermal decomposition of both pure and Ti-doped aluminohydrides. Most likely, the presence of a titanium hydride phase in the catalyst is responsible for the catalytic effect of Ti-additives. Furthermore, ball-milling promotes chemical and phase transformations of solid alanates by enhancing mass transfer in the material and creating high-pressure spots where pressure-driven chemical reactions can take place.

Cis-(Ph3P)2PtCl2 and cis-(Ph3P)2PtCO3 were prepared mechanochemically from solid reactants in the absence of a solvent; cis-(Ph3P)2PtCl2 was obtained in 98% yield after ball-milling of polycrystalline PtCl2 and Ph3P; the mechanically induced solid-state reaction of cis-(Ph3P)2PtCl2 with an excess of anhydrous K2CO3 produced cis-(Ph3P)2PtCO3 in 70% yield; the formation of transition metal complexes as a result of mechanochemical solvent-free reactions has been confirmed by means of solid-state 31P MAS NMR spectroscopy, X-ray powder diffraction and differential thermal analysis.

Phosphonium salts have been prepared during high-energy ball-milling of triphenylphosphine with solid organic bromides; the reactions occur at ambient conditions without a solvent; in the case of 2-bromo-2-phenylacetophenone the reaction in a solution usually produces a mixture containing both the C-phosphorylated and O-phosphorylated compounds, while the solvent-free mechanically induced transformation results in the thermodynamically favorable C-phosphorylated product; the occurrence of the observed transformations during mechanical processing of solid reactants is confirmed by the solid-state 31P NMR spectroscopy and X-ray powder diffraction.

Cis-(Ph3P)2PtCl2 and cis-(Ph3P)2PtCO3 were prepared mechanochemically from solid reactants in the absence of a solvent; cis-(Ph3P)2PtCl2 was obtained in 98% yield after ball-milling of polycrystalline PtCl2 and Ph3P; the mechanically induced solid-state reaction of cis-(Ph3P)2PtCl2 with an excess of anhydrous K2CO3 produced cis-(Ph3P)2PtCO3 in 70% yield; the formation of transition metal complexes as a result of mechanochemical solvent-free reactions has been confirmed by means of solid-state 31P MAS NMR spectroscopy, X-ray powder diffraction and differential thermal analysis.

We describe the nearly quantitative preparation of phosphorus ylides and the Wittig reaction occurring in the solid sate during high-energy mechanochemical processing. Initial insights into the details of the discovered chemical transformations indicate that high-energy mechanical processing supports the interaction of reacting centers by breaking crystallinity of the reactants and by providing mass transfer without a solvent.

Polycrystalline LiAlH4 transforms into polycrystalline Li3AlH6 and Al during short time (5 min) ball-milling with 3 mol% TiCl4 at room temperature; solid-state rearrangement of tetrahedral [AlH4]− into octahedral [AlH6]3− at ambient conditions was previously unknown; this transformation does not occur during ball-milling of pure LiAlH4 or in the presence of 3 mol% TiCl4 without mechanochemical treatment.