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Crown ethers were discovered in 1967 and since then, the interest in their properties and applications increased. Crown ethers have specific molecular shapes and planar conformation, but the flexibility of the ring can change depending on the interactions with guest ions or molecules. The cation encapsulation in the 18-crown-6 ether (18c6) cavity is well-known in solution chemistry, however, the supramolecular recognition may also be accomplished in the solid state. Our goal was to explore the complexation of 18c6 with potassium salts in a ball mill and test the reactivity of the formed [18c6K]OH complex. The successful complexation was evidenced by powder X-ray diffraction (PXRD) and IR spectroscopy. The Cambridge Structural Database served as a tool for searching the previously reported crystal structures and matching them with experimentally observed ones, while a new crystal structure of a monohydrate complex of the 18c6 and the KCl ion pair was solved and refined against laboratory PXRD data. It was found that the initial squashed conformation of 18c6 molecules in the pure solid opens with milling. The catalytic properties of [18c6K]OH complex were tested in two organic reactions, the Henry reaction and the nucleophilic aromatic substitution reaction. The results indicate the potential of using crown ether complexes in solid-state catalysis where their use is still underexplored.

The ability to predict mechanochemical reaction pathways and kinetics based on the mechanical energy input as well as the characteristics of the targeted chemical reactivity is required for efficient experimental planning. While we have recently established linearity between energy input and reaction progress in a purely mechanochemically activated reaction, we have here tested the application of the classical solution- based Hammett correlation in mechanochemical Schiff base formation from p-nitrobenzaldehyde and differently substituted anilines. Tracking chemical transformations in real time using in situ Raman spectroscopy enables the examination of the connection between chemical, rheological and kinetic factors. It was shown that the properties of reaction material such as hardness and density affect the elasticity of the collisions in a ball mill and the different course of the reaction. The linear dependence of the reaction probability and the Hammett constants derived from the solution indicates that the current models borrowed from physical-organic chemistry can be exploited to further the understanding of milling reactions.

Solution-based physical organic chemistry was marked by the development of Hammett correlation, which further served as a major tool for deciphering the mechanisms of organic reactions in solution. If applicable to mechanochemical reactions, it will provide support for understanding the reaction mechanisms and expansion of this important synthetic methodology. As a model system to test the validity of the Hammett equation under mechanochemical conditions, we focused on imine formation from an aromatic aldehyde and anilines. Using in situ Raman reaction monitoring and kinetic analysis, we find a linear relationship between the reaction probability and Hammett constants indicating that this classical concept of chemical reactivity is valid for reactions conducted by ball milling and could prove useful for optimization of mechanochemical reactions. The Hammett plot showed that the imine formation is sensitive to the nucleophilicity of the aniline partner with the reaction probability increasing with stronger electron donor substituents, as expected. We further explore reaction mechanism of imine formation on a catalysed reaction, in a contrast to the otherwise facile imine preparation by neat grinding.

Solid-state synthesis by mechanochemistry serves as an alternative to solution synthesis, but for a wider application within the framework of green chemistry, detailed investigations about reaction mechanisms at the molecular level are crucial [1]. One of current disadvantages of mechanochemistry is insufficient understanding of the influence of milling parameters on energy transfer during ball milling. In this paper, simple one-step trimerization of nickel(II) dibenzoylmethane was used as a model system to systematically examine by in situ Raman spectroscopy the effect of the milling frequency, and the material and mass of milling balls on the mechanochemical oligomerization reaction rate (Figure 1). By varying milling parameters, we have modified energy input required for the chemical transformation leading to different reaction profiles. Based on numerical simulations of the milling processes, a linear relationship was established between the reaction rate and the energy dose absorbed by the sample. Consequently, the energy dose increases with the frequency of impacts, mass and the average ball velocity, but decreases with the hardness of milling media to the minimum energy needed to initiate chemical conversion.

Cucurbit[n]urils (n = 5-10) are rigid host molecules with hydrophobic cavities that can bind guests in 1:1, 2:1, or 1:2 complexes and have been used previously to bind hydrophobic guests in water often with extreme binding affinities up to 7.2 x 1017 M−1 .[1-3] Solvent-free mechanochemical synthesis (ball milling) has been shown to be a useful method for the preparation of inclusion complexes with cucurbit[7]uril and adamantane and phenyl derivates as model molecules of guests.[4] Therefore, we researched various phenylenediamine derivatives and ferrocene inclusion complexes with Cucurbit[n]uril. Studies included mechanochemical formation of inclusion complex in vibrational mill. In situ monitoring of grinding reactions by Raman spectroscopy enabled direct insight into the successful formation of the HostGuest complex and the mechanochemistry of grinding.[5]. Host-guest complexation in the solidstate was studied and characterized by X-ray powder diffraction, FTIR, NMR spectroscopy, and differential scanning calorimetry.

Primjena mehanokemijskih postupaka na industrijskoj skali ograničena je radi nepotpunog razumijevanja mehanizama mehanokemijskih reakcija. U ovom radu istraživan je utjecaj frekvencije mljevenja, materijala i mase kuglica na mehanokemijsku oligomerizaciju niklovog(II) dibenzoilmetanata primjenom Ramanove spektroskopije in situ. Pripravljeni spojevi karakterizirani su rendgenskom difrakcijom, XRD, i termogravimetrijskom analizom. Izabrani modelni sustav jednostupanjska je reakcija trimerizacije čija se brzina povećava porastom frekvencije mljevenja, korištenjem većeg promjera kuglica za mljevenje kao i materijala veće gustoće (ahat < cirkonijev dioksid < nehrđajući čelik < volframov karbid). Praćeni parametri bitno utječu na prijenos energije te reaktivnost sustava što je i potvrđeno kinetičkim reakcijskim profilima i numeričkim simulacijama. Dobiveni rezultati od velike su važnosti za optimizaciju mehanokemijskih procesa kao i njihovo dublje razumijevanje.

The collected set of results clearly illustrates the potential of mechanochemical treatment for carrying out interzeolite conversion reactions in a rather short period of time and with significantly reduced water content with respect to conventionally performed reactions of this type. Evidently, this makes the ball milling procedure more ecologically sound than the classic method of interzeolite conversion. Further, the phase composition and the properties of the formed material arise as an outcome of the subtle interplay of kinetic and thermodynamic factors. They ensue as a consequence of numerous events (condensation, (de)polymerization, (de)protonation, etc.) taking place concurrently in the synthesis mixture. It is expected that the findings reported here will provide guidelines for designing and conducting further ball milling experiments to achieve even more environment-friendly process of interzeolite conversion.

Zeoliti su mikroporozni kristalni materijali koji se sastoje od TO4 tetraedara koji grade supramolekulske mreže s dobro definiranim kanalima i šupljinama. Danas su poznata 253 različita strukturna tipa zeolita. Našli su široku primjenu kao ionski izmjenjivači, adsorbensi i katalizatori, zbog čega su vrlo značajni materijali u industriji. Klasične metode priprave zeolita obično uključuju korištenje solvotermalnih metoda i uvjeta koje traju nekoliko dana ili čak tjedana i troše puno resursa i vremena.[1] S ciljem da se pronađu jeftinije i brže metode sinteze zeolita, koristili smo termički kontroliranu mehanokemiju – novo razvijenu tehniku koja omogućuje izvođenje mehanokemijskih reakcija pri povišenim temperaturama do 250 °C. [2] U ovom smo radu pokazali kako se mljevenjem zeolita Y s različitim bazama (kalijevim, natrijevim i cezijevim hidroksidom), s i bez vode, pri 110 °C produkt može dobiti u samo nekoliko minuta, dok solvotemalnim metodama takav produkt ne nastaje niti nakon dva dana. Uz pomoć in situ PXRD mjerenja napravljenih na Deutsches Elektronen- Synchrotronu (DESY), identificirali smo intermedijerne faze, finalne produkte te vremena njihovog nastajanja, dajući mogućnost provođenja selektivnih reakcija interzeolitne konverzije zeolita Y kako bi se priredili drugi zeoliti.

Organohalides are very valuable synthetic precursors, and the transformation of carbon- halogen (C–X) bond is often one of the synthetic steps in the preparation of numerous organic and natural compounds, pharmaceutically active substances, and new materials. Their preparation is traditionally limited to solvent-based synthetic procedures, and nowadays solid-state synthetic methods are increasingly being developed as their greener alternative, with mechanochemical reactions being the most prominent. Within this work, a mechanochemical procedure for regioselective halogenation of azobenzene C-H bond using PdII catalyst has been developed and optimized. The mechanism of this process has been studied by in situ Raman spectroscopy accompanied by ex situ NMR and PXRD experiments. A strong effect of solid and liquid additives on the reactivity of the catalytically active PdII species and intermediates has been established. Several possible palladacyclic intermediates have been synthesized and characterized, and their role in palladium-catalyzed ortho-halogenation of aromatic substrates has been discussed. Based on our results, a multistep reaction mechanism of this transformation has been proposed.

Organohalides are extremely valuable synthetic precursors, and the transformation of the carbon- halogen bond is on many occasions one of the synthetic steps in the preparation of numerous organic and natural compounds, pharmaceutically active substances, new materials, catalysts, etc. Traditional solvent-based methods often require reactions with elemental halogens, harsh reaction conditions, and metal catalysts which are in many cases additionally hampered by difficult-to- control selectivity. As a greener alternative to solvent- based reactions, chemical transformations in the solid-state have drawn increasing attention among chemists due to the unique benefits which the solid-state methods provide in terms of sustainability, reaction times, yields, solubility, selectivity, and chemical reactivity. In this work we present optimized conditions for solvent- and metal-free regioselective halogenation of 4’-(N, N dimethylamino)-4- nitroazobenzene and 4 methoxyazobenzene by mechanochemistry. This mild and environmentally friendly approach allowed the selective preparation of halogenated derivatives and led to an unexpected product. The reactions were monitored by in situ Raman spectroscopy which in combination with ex situ NMR, IR, and X-ray experiments allowed characterization of the involved reaction species and direct insight into the reaction dynamics.

Novija istraživanja pokazala su sposobnost N- alkiliranih ferocen-kinolinskih konjugata da inhibiraju određene tumorske stanice. Ferocen- uracil konjugati pokazuju sličnu biološku aktivnost, no velika lipofilnost takvih spojeva ograničava njihovu primjenu. Ciklodekstrini su pokazali dobre rezultate u formiranju kompleksa s lipofilnim spojevima kako bi poboljšali njihovu topljivost u vodi i time bolju biodistribuciju i farmakokinetička svojstva lijekova. Kompleksiranje ferocen derivata provedeno je najprije otopinski s ferocenskom kiselinom u puferu pH 7, 4 te je okarakterizirano UV-Vis spektroskopijom iz čega je dobivena konstanta stabilnosti 3, 6. Daljnja ispitivanja provedena su novijom metodom – sinteza u čvrstom stanju u mlinu. Prednosti takve metode su korištenje vrlo malih do nikakvih količina otapala što pridonosi bržoj, manje toksičnoj i jednostavnijoj sintezi spojeva. Nastajanje inkluzijskog kompleksa ferocenskog derivata s beta-cyclodextrinom provedeno je mljevenjem u vibracijskom mlinu. Inkluzijski kompleks u čvrstom stanju okarakteriziran je NMR spektroskopijom, IR i X-ray difrakcijom praha.

Mechanochemistry is becoming recognized as a technique because it can promote solid-state reactions quickly and quantitatively, even on a large scale, but is also enabling access to processes and products usually not feasible in solution [1, 2]. Multicomponent solids, like cocrystals have been recognized and used to execute solid state reactions selectively and efficiently. Building on these recent advances, herein we employ real-time in situ Raman spectroscopy monitoring [3, 4] to explore the possibilities of manipulating the reaction kinetics and chemical reactivity of the Knoevenagel condensation in solid state. We emphasize in particular reaction paths and product selectivity that can be explored in the solid state by applying principles of crystal engineering [5, 6] through the use of polymorphs, desmotropes, cocrystals, or salts.

Graphene quantum dots (GQDs) are a latest zero- dimensional (0D) member of the carbon family, consist of single to few layers of graphene sheets with lateral dimensions of

The miniaturization and persistent presence of smart devices has led to their mass production, with digital inkjet printing technology standing out as a simple, fast, and economical manufacturing method. Such an approach requires the formulation of an electrically conductive ink based on dissolving and stabilizing the functional material in a suitable solvent or solvent mixture. Due to its outstanding electrical conductivity and mechanical durability, intensive research has been focused on the manufacturing techniques of graphene. Presented here is a study on the preparation and optimization of graphene inks suitable for inkjet printing on a PET substrate. We have adopted a facile mechanochemical route for single and two layered graphene nanosheet fabrication, by melamine induced exfoliation in a planetary ball mill. Stability of the melamine intercalated graphene nanosheets (M-GNs) was evaluated in several solvents. Finally the M-GNs were dispersed in a mixture of water and ethanol with the aid of commercial polymeric dispersants Solsperse 20000 and 12000S at a concentration of 3 mg/mL. Surface tension, viscosity and density of this ink were optimized to match the inkjet printer requirements. Dynamic light scattering measurements revealed an adequate average particle size of 200 nm. Multiple layers of the ink were printed and electrical properties of the samples were evaluated. The printed features were exposed to intense pulsed light (IPL), thereby lowering their sheet resistance by an order of magnitude.

Recent research shows that ferrocene uracil derivatives have biological activity. However, their high lipophilicity limits the application. It is known that cyclodextrins show abillity to improve drug water solubility by binding the hidrophobic moiety of the molecule inside of its cavity, such as ferrocene.2 Ferrocene shows different binding orientations as well as binding constants for alpha, beta and gama cyclodextrine in water.3 Environment of ferrocene can influence their binding to cyclodextrines. Therefore, we researched various ferocene uracyl derivatives with different R’, R groups and studied their binding ability with α-cyclodextrin, β- cyclodextrin, γ-cyclodextrin and modified (2- hydroxypropyl)-β-cyclodextrin in water. Characterisation was preformed using UV-Vis spectroscopy. Titrations were used to calculate binding constants that show range between.

Graphene quantum dots (GQDs) have attracted significant attention due to its intriguing physicochemical properties which makes it a good material for potential applications in bioimaging, sensing, solar cells, photovoltaic devices, photocatalysis and white-light- emitting diodes [1]. Nevertheless, industrial GQDs synthesis is strenuous due to the toxicity and longevity of thus far invented processes [2]. Therefore, a facile and highly reproducible approach for the large-scale generation of GQDs with minimal surface defects is required. Herein we describe environmental- friendly, solid-state mechanosynthesis of GQDs.

Numerical simulations for precise temperature profiles of milling reactions revealed dominant contribution of frictional heating, while reaction enthalpy remained negligible., Mechanochemical reactions by ball milling are becoming increasingly popular across a wide range of chemical sciences, but understanding and evaluation of temperature during such processes remains a persistent challenge, especially for organic and metal–organic materials. Here, we describe the first methodology for precise real-time measurement of sample temperature during mechanochemical transformations. Using this technique coupled with real-time in situ reaction monitoring by synchrotron X-ray diffraction and numerical simulations of heat flow, we have shown that the temperature profiles of mechanochemical reactions are dominantly determined by the energy dissipated through friction between the sample and the moving milling assembly, while the reaction enthalpy will usually be comparatively insignificant. With the changes in composition during mechanochemical reactions, frictional properties of the milled material change, leading to either better or worse energy absorption upon collisions in the process of milling. This approach explains unexpected and rapid temperature drops during exothermic transformations of ZIF-8 polymorphs. Since reaction kinetics are highly sensitive to changes in temperature, precise temperature profiles provided here will be mandatory to understand kinetics and its changes during milling, and will aid in developing the comprehensive model of mechanochemical reactivity.

The milling ball is the catalyst. We introduce a palladium‐catalyzed reaction inside a ball mill, which makes catalyst powders, ligands, and solvents obsolete. We present a facile and highly sustainable synthesis concept for palladium‐catalyzed C−C coupling reactions, exemplarily showcased for the Suzuki polymerization of 4‐bromo or 4‐iodophenylboronic acid giving poly(para ‐phenylene). Surprisingly, we observe one of the highest degrees of polymerization (199) reported so far.

It has been recently shown that N-alkylated ferrocene quinoline conjugates exhibited inhibitory effects on selected tumor cell lines. Similar biological activity has been demonstrated by ferrocene thymine conjugates. However, their application is limited, due to the high lipophilicity of these compounds and the poor solubility in water. Therefore, to solve these obstacle inclusion complexes with cyclodextrin have proved to be useful because they allow better solubility in water, and thus better bio-distribution and pharmacokinetic properties of some drugs. The formation of inclusion complex of ferrocene derivatives with α- and β-cyclodextrin was carried out mechanochemical by ball‐milling. The solid- state grinding approach to preparing complexes is a newer method within green chemistry approach that draws great attention. Host-guest complexation in the solid state was studied and characterized by NMR spectroscopy, IR and X-ray powder diffraction.

Graphene oxide (GO) is single-atom carbon layer, combination of unsaturated benzene rings and aliphatic heterocycles containing hydrophilic oxygen groups. Lately, GO has attracted significant attention, mostly as a potential material for mass production of graphene, but also for its potential for various other applications such as electronic and energy storage devices, biosensors, optical materials, electronic and energy storage devices and photocatalysts. A great advantage of GO are its tunable physicochemical properties which depend upon the degree of oxidation. Conventional chemical synthesis of GO mostly prefers the Hummers method. As a result, laboratory- and industrial-scale chemical synthesis of GO are inherently generating toxic waste. It is therefore essential to find greener and cheaper ways of its production. Here, we report versatile and eco-friendly approach to prepare high quality GO by use of mechanochemical ball milling of graphite in presence of KMnO4 and the stoichiometric amount of sulfuric acid. We have examined how various conditions of mechanochemical synthesis affect on the GOs degree of oxidation, which we have been able to obtain in the range from 17 % to 62 %. Prepared materials were characterised by powder X-ray diffraction, Raman spectroscopy, thermogravimetric analysis, FTIR spectroscopy and SEM/EDS microscopy.

In the last decade, graphene and graphene oxide (GO) have been intensively investigated due to their excellent electronic, optical, mechanical, thermal properties and their wide range of applications such as electronic and energy storage devices, optical materials, biosensors and water treatment. GO is single- atom carbon layer containing range of reactive oxygen groups upon which its structure and properties directly depend. Nevertheless, large-scale production of high quality GO is still a challenging task for researchers and since industrial-scale chemical synthesis of GO are inherently generating large amount of toxic waste, it is more than necessary to find a new, cleaner and cheaper way of its production. [1] However, mechanochemistry is becoming more disseminated as a technique because it can promote reactions between solids, with either no added solvent or only minimal amounts. Moreover, it offers more sustainable, environmental friendly and energy- facilitatied synthesis pathways, which could be the way to reduce or completely remove our current dependence on solvents in GO production. [2] Herein, we present versatile and eco-friendly approach for mechanochemical preparation of GO. Furthermore, we also present it is possible to obtain 3D graphene hydro- (GHs) and aerogels (GAs) via one-step hydrothermal method using mechanochemically prepared GO. GHs are a new class of 3D carbon monoliths holding promise for applications as diverse as electrochemical energy storage, tissue engineering, CO2 capture and pollutant adsorption. They consist of entangled layers of graphene, albeit they partially retain the excellent properties of monolayer graphene.

Cyclopalladated complexes or palladacycles are successfully applied in many areas of material science and biological chemistry. Their preparation is usually performed in solution but number of reports on the solid-state synthesis of these organometallic complexes is steadily growing. Recently, our group reported a successful solid-state synthesis of azobenzene palladacycles in a ball mill that was followed by a detailed mechanistic study of C–H bond activation in azobenzene by various palladium (Pd) precursors, i.e. polymeric PdCl2, monomeric [PdCl2(MeCN)2], trimeric [Pd(OAc)2]3 and ionic [Pd(MeCN)4][BF4]2. Herein we report on X-ray diffraction identification and characterization of palladacycles obtained by C–H bond activation in 4-chloro-4’-(N, N- dimethylamino)azobenzene by various Pd(II) precursors in a ball mill (Figure 1). Each type of the employed Pd(II) precursor afforded a structurally different mono- and/or dipalladated complex. Structural analysis shows that all monopalladated products have a palladated p-(N, N-dimethylamino)phenyl ring, which agrees with a regioselective solid- state reaction. Reactions with acetate and chloride Pd(II) precursors afford dimeric and monomeric dicyclopalladated complexes, respectively. Obtained results show a strong influence of the ancillary ligands on the molecular structure of the analyzed palladacycles and support the proposed mechanistic scheme for double palladation of azobenzenes in a ball mill by various Pd(II) precursors.

C–H bond activation is often the first step in metal-catalyzed functionalization of the organic compounds usually performed using palladium (Pd) catalysts. Number of reports on successful solid state C–H bond functionalization by ball milling is growing, but no deeper insight into their mechanism has been obtained. Recently, a detailed mechanistic study of the solid-state activation of two C–H bonds in an asymmetric azobenzene substrate by Pd(II) chloride precursors, e.g. PdCl2 and PdCl2(MeCN)2, has been elucidated using in situ collected Raman spectra and ex situ spectroscopic and synthetic experiments. Results support a regioselective two-step reaction in which each step involves a coordination of the substrate to the Pd(II) precursor forming an adduct that then undergoes the C–H bond cleavage. Herein we report single- crystal X-ray diffraction experiments that allowed for structural identification of the azobenzene reactant as well as reaction intermediates and products of the double C–H bond activation in the solid state (Figure 1). Structural analysis proved as a key step toward determination of the reaction course and supported the proposed mechanism of the C–H bond activation in the azobenzene substrate, which was found analogous to the proposed mechanism for these reactions in solution.

Recent evolution of solid-state synthetic methods has led to their prompt utilization in a metalcatalyzed functionalization of organics. An important class of catalytic reactions are palladiummediated processes for which the C–H bond activation is identified as the first mechanistic step in a solution. However, a mechanistic study of the solid-state C–H bond activation is still lacking. We have studied a mechanism of the ligand- directed C–H bond activation by various Pd(II) catalysts under mechanochemical conditions by in situ Raman monitoring and ex situ PXRD, NMR and IR methods. Selected Pd(II) precursors, PdCl2, PdCl2(MeCN)2, [Pd(MeCN)4][BF4]2 and [Pd(OAc)2]3, have been employed for solid-state activation of C–H bonds in an azobenzene substrat. Raman monitoring has provided direct probing of the reaction mechanism and revealed how liquid (DMF, MeCN, AcOH and H2O) as well as solid additives (NaOAc and NaBF4) influence the reactions.

The use of mechanochemistry continues to grow due to its efficiency, selectivity and greener way in obtaining desired products. Inability to directly and in real- time monitor reaction progress of milling reactions, without the need to obstruct the milling process, was historically considered as a main drawback of mechanochemistry. This has been recently addressed by advanced synchrotron powder X-ray diffraction1 and laboratory Raman spectroscopy2 in situ monitoring methods which provided a direct insight into physical and chemical changes in reaction mixtures. Utilization of mechanochemistry in pharmaceutical industry is driven primarily by increasing need to create more sustainable drug manufacturing processes. Here we present mechanistic study of mechanochemical cocrystal synthesis of nicotinamide (vitamin B3) and L-ascorbic acid (vitamin C). Using ethanol and methanol as additives in milling 1:1 reaction mixture we have obtained two vitamin B3:C cocrystal polymorphs. Kinetically favored polymorph I is known from the literature3 and is in fact intermediate in the formation of previously unknown polymorph II which is thermodynamically more stable. We have successfully solved crystal structure of B3:C cocrystal polymorph II from synchrotron powder X- ray diffraction data. Both polymorphs remained in their respective solid forms even after 6 months of shelf life. Thermodynamic relationship of cocrystal polymorphs was determined by competitive slurry experiment which resulted in pure cocrystal polymorph II. Scaling up manufacturing process for both cocrystal polymorphs up to 10 grams and 100 grams has been achieved using planetary mill and twin screw extruder, respectively. Mechanochemically obtained cocrystal polymorphs exhibit excellent tableting properties compared to their reactants. This is important since L- ascorbic acid is famous for having poor compactible properties. Solution cocrystalization experiments resulted always in kinetically favored polymorph I, whereas the thermodynamically more stable polymorph II is available exclusively by mechanochemical milling. Acknowdlegements: Financial support from the Croatian Science Foundation (Grant No. UIP-2014-09-4744) is greatly appreciated.

For the first time, in situ monitoring of uninterrupted mechanochemical synthesis of two bimetallic amidoboranes, M2Mg(NH2BH3)(4) (M=Li, Na), by means of Raman spectroscopy, has been applied. This approach allowed real-time observation of key intermediate phases, and a straightforward follow-up of the reaction course. Detailed analysis of time-dependent spectra revealed a two-step mechanism through MNH2BH3 center dot NH3BH3 adducts as key intermediate phases which further reacted with MgH2, giving M2Mg(NH2BH3)(4) as final products. The intermediates partially take a competitive pathway toward the oligomeric M(BH3NH2BH2NH2BH3) phases. The crystal structure of the novel bimetallic amidoborane Li2Mg(NH2BH3)(4) was solved from high-resolution powder diffraction data and showed an analogous metal coordination to Na2Mg(NH2BH3)(4), but a significantly different crystal packing. Li2Mg(NH2BH3)(4) thermally dehydrogenates releasing highly pure H-2 in the amount of 7 wt.%, and at a lower temperature then its sodium analogue, making it significantly more viable for practical applications.

A series of single- and bimetallic amidoboranes and their complexes with ammonia borane were prepared by ball milling from ammonia borane and corresponding metal hydrides. Products are characterised by means of IR spectroscopy and powder XRD. Dehydrogenation was followed by DSC and variable temperature Raman spectroscopy. All of the prepared systems dehydrogenate at considerably lower temperature with respect to ammonia borane.

New zinc containing metal-organic framework (Zn- truxillate) has been synthesized under mild hydrothermal conditions: temperature of 120 °C and reaction time of 72 h. The obtained product (small light-brown crystals) was characterized using several analytical methods, such as powder X-ray diffraction, infrared spectroscopy (FTIR), thermal methods (TG, DTG).

Jedan od načina istraživanja pojedinih kemijskih koncepata temelji se na izboru odgovarajućeg konkretnog eksperimentalnog ili teoretskog modela na kojem se ispitivani koncept ili učinak dobro razabiru. U epistemologiji se takvom pristupu obično pridaje termin case study. Sustavna istraživanja kemijskog ponašanja C-nitrozo- spojeva, koja su posljednjih godina provedena u našem laboratoriju, pokazala su da se taj molekulski sustav može iskoristiti kao višestruki kemijski model (case study) za paralelno istraživanje niza temeljnih kemijskih koncepata, selektivnosti, samoorganiziranja, reakcijskih mehanizama u čvrstom stanju, fotokromizma i molekulske logike. Iz niza navedenih primjera, koji se odnose na istraživanja u našem laboratoriju u posljednjih osam godina, razabire se univerzalnost molekulskog modela koji uključuje dimerizacije aromatskih nitrozo-spojeva.