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International audience; The special case of the stacking of trihalogeno mesitylene (TXM) molecules has been investigated. Below 300 K, these molecules lead to needle shaped crystals in a triclinic arrangement. Thanks to DFT computations and an empirical atom-atom interaction model this packing mode has been rationalized. Aggregates of TXM molecules differently packed have been considered, namely dimers and trimers of type A, the molecules being piled one over the other along the axis a, and dimers B and trimers B, the molecules lying in the same bc plane. From the computations, it appears that the stabilizing energy of formation of a dimer of two molecules piled along a is several times larger than the energy gain obtained from the formation of a dimer of two neighbors in the bc plane. It has also been found that the energy of formation of a trimer of type A is approximately twice the energy of formation of a dimer A, so that an additive rule occurs. These conclusions are in perfect agreement with the experimental observations of the shape of the crystals obtained by crystallization from a super-saturated solution of TXM in an organic solvent long needles with TXM molecules stacked along the axis a have always been obtained and never thin plate-like crystals. © 2019 Elsevier B.V.

A new heterogeneous polymer supported solid phase oxovanadium(IV) catalyst was synthesized successfully. The designed catalyst furnished excellent results in the oxidation reactions of various aromatic alkanes, e.g. toluene, para-xylene, mesitylene. The polymer supported vanadium complex was proved also an efficient catalyst for the oxidation of aromatic alkenes, like substituted styrenes, trans-stilbene, etc. under mild reaction conditions. The supported catalyst was nicely elucidated by SEM-EDAX, TGA, FT-IR and UV–Vis spectral analysis. The catalytic activity was tested in the presence of an environment-friendly oxidant, 30% aqueous H2O2 during the oxidation of broad range of substrates. Another important fact is that the designed oxovanadium(IV) catalyst is heterogeneous in nature. Moreover, the newly synthesized oxovanadium(IV) complex exhibited a notable recoverability and it could be recycled up to six runs devoid of any prominent reduction in catalytic behavior.

Two-dimensional (2D) layered zeolites are new forms of 3D zeolite frameworks. They can be pillared to form more open porous structures with increased access for reactants that are too big for the micropores of zeolites. The current pillaring procedure, however, requires intercalation of pillaring precursors by dispersing 2D zeolite in an alkoxide liquid and hydrolizing entrapped alkoxide to form inorganic oxide pillars in an aqueous alkaline solution. Both steps use excess solvents, generate significant waste, and require multiple synthesis and separation steps. Here we report a vapor-phase pillarization (VPP) process to produce pillared zeolites from 2D layered zeolite structures. The VPP process has ∼100% efficiency of alkoxide usage in the intercalation step, requires less (and, in some cases, zero) water addition in the hydrolysis step, does not require separation for product recovery, and generates no liquid waste. Furthermore, synthesis of pillared zeolites via the VPP process can be accomplished within a single apparatus with one-time operation. The pillared zeolite prepared by the VPP method preserved the zeolitic layered structure as well as acidity and showed enhancement in catalytic alkylation of mesitylene with benzyl alcohol compared to 2D layered zeolite without pillarization treatment.

We reported a strategy to synthesize MFI zeolites with tunable properties by tailoring organic structure-directing agents (OSDAs) under the hydrothermal conditions. The tailored surfactants were obtained by tuning the structure of Gemini-type Cph-10-6-6 and Bola-type BCph-10-6-6, including alkyl tail chains, ammonium groups and alkyl middle chains. The textural property, morphology and acidity of resulting MFI zeolites were characterized by a complementary combination of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption-desorption isotherms and FTIR spectra of pyridine adsorption. Moreover, the correlation between the OSDAs’ composition and the inorganic precursor in the fabrication of zeolite framework was investigated by DFT calculations in this study. The catalytic performance of the resulting MFI samples was investigated by the alkylation of mesitylene with benzyl alcohol. The results revealed that the OSDAs without ammonium groups only leaded to form the micro-structure of zeolites, but the OSDAs with ammonium groups can induce the formation of micro- and meso-structure simultaneously, regardless the OSDAs ended with or without alkyl tail chains. In addition, the resulting MFI zeolites showed an improved catalytic activity in alkylation of mesitylene with benzyl alcohol due to the enhanced pore accessibility, the acidity (Bronsted/Lewis) controlled the activation of benzyl alcohol, and the ratio of external surface area (Sext/SBET) governed the selectivity of alkylation reaction. As a result, tailoring the structure of OSDAs can pick another strategy to synthesize MFI zeolites with tunable zeolite structure and catalytic performance.

Separation of 1-butanol from the model fermentation broth (98 wt% water + 2 wt% ABE, acetone: 1-butanol: ethanol = 3: 6: 1) using liquid-liquid extraction (LLE) was investigated in this paper. This investigation involved multi-scale simulations from ab initio calculation to process simulation. Firstly, suitable extractant was screened from ionic liquids (ILs) combined of 30 anions and 40 cations using conductor-like screening model for real solvent (COSMO-RS) model. Meanwhile, the equilibrium experiment of the system ABE solution+selected IL was conducted to verify the screening result. From the screening, [HMIM][FEP] was found to be an optimal extractant and the experimental data confirmed this screening result with a deviation of 3.54%. The continuous hybrid process consisting of extraction and distillation section with the selected IL was also simulated and compared with a referenced process selecting mesitylene as extractant using Aspen Plus to investigate the performance of IL in real industry. The simulated results showed that a higher mass purities and yields of acetone (≥99.5 wt%), ethanol (≥99.5 wt%) and 1-butanol (≥99.9 wt%) could be obtained with much lower capital cost and energy consumption when the extractant was compared from [HMIM][FEP] to mesitylene. The extractant consumption and the energy consumption could lower 10% and 4.4% in total, respectively. The ab initio calculation enabled a deep insight on the mechanism of IL in extraction. Obviously, the results uncovered by the ab initio calculation showed that interaction between IL and 1-butanol was much stronger than mesitylene.

It has been found that catalytic deoxygenation of triglycerides is a viable pathway for obtaining renewable liquid fuels to contribute to meet the global energy demand. In this study, SBA-15 mesoporous silica was synthesized in a pure form and modified with mesitylene (TMB) as a swelling molecule (SBA15-TMB). Catalysts with 0.5, 1.5 and 3.0 wt% Pd were synthesized and tested by deoxygenation of stearic acid (SA), obtaining initial conversions of 68–98% that decreased to 36–73% after 6 h time-on-stream. The most abundant product was n-heptadecane, with a selectivity of ~ 90%. The most active catalyst evaluated with SA was 3.0 wt% Pd over unmodified SBA-15 (30Pd/SBA-15). Subsequently, fresh and regenerated 30Pd/SBA-15 catalysts were tested with waste cooking oil (WCO) feed, obtaining conversions of 74 and 72%, respectively, but the fresh catalyst allowed a better oxygen removal (91%. Additionally, commercial Pd(10wt %)/C catalyst was evaluated, obtaining results comparable to those for the regenerated 30Pd/SBA-15 catalyst. The main WCO reaction product for all catalysts was a diesel fraction (C12-C21), and the quality of the products was not very different, following the order: Pd(10wt %)/C > 3.0Pd/SBA-15-regenerated > 3.0Pd/SBA-15-fresh. The results obtained indicate that shynthetized catalysts of this study are promising for obtaining renewable diesel from low-cost feeds while using low hydrogen consumption.

The use of silver trifluoromethanesulfonate (silver triflate, AgOTf) as a halide abstraction reagent is pervasive in organometallic chemistry. However, recent reports suggest a “hidden” Bronsted acid lurks within it that may catalyze purported metal-based catalysis. Presented herein are new reactions that are either catalyzed or promoted by the “hidden” acid, generated upon silver triflate degradation. 1-Phenylethanol dehydrates to styrene (1) upon reaction with AgOTf at 90 °C over 24 h, which slowly coverts to the vinyl hydrovinylation product (E)-1,3-diphenyl-1-butene, (2, 64%) over several days. While dehydration was observed with a number of benzylic alcohols to yield Zaitsev selective olefins, only 1-phenylethanol affords vinyl hydrovinylation products. Dehydration was not observed for primary and secondary alcohols, suggesting an acid catalyzed E1elimination reaction mechanism is at play. The degradation of silver triflate was found to be the source of the “hidden” Bronsted acid, which demonstrated a dependence on the presence of light and oxygen. In the absence of light and oxygen, dehydration of 1-phenylethanol was severely stunted and 2 is not formed, but instead the ether product, oxy-bis(ethane-1,1-diyl)dibenzene (3), is afforded. The mesitylene internal standard also reacts with the in situ formed styrene to produce 2-(1-phenylethyl)mesitylene (4) through acid catalyzed electrophilic aromatic substitution. These reactions were monitored (products characterized) by GC-MS and/or 1H NMR spectroscopic methods. We present herein the details of these reactions and our characterization methods.

Reactions of divalent metal salts with 4,4-oxybis(N-(pyridine-4-yl)-benzamide), L, and naphthalene-1,4-dicarboxylic acid (1,4-H2NDC) in various solvents gave [Zn(L)(1,4-NDC)·H2O]n, 1, [Cd(L)(1,4-NDC)(H2O)·MeOH]n, 2, and [Co(L)(1,4-NDC)(H2O)0.5·MeOH]n, 3, which have been structurally characterized. Complexes 1–3 show eight-fold interpenetrating frameworks with the dia topology, which exhibit porosities substantiated by CO2 adsorption, whereas 1 and 2 manifest stability in aqueous environments and show high selectivity toward sensing of mesitylene molecules and Fe3+ ions with low detection limits and good reusability up to five cycles.

Mesitylene was used as a core in seven new tritopic nitrogen containing linkers. Three of the linkers, each containing three nitrile groups, were obtained through Suzuki, Sonogashira and Heck-type coupling reactions. Next, these were converted to tetrazol-5-yl moieties by the cycloaddition of sodium azide to the nitrile functionalities. The last linker, containing three 1,2,3-triazol-4-yl moieties, was synthesized by the Huisgen cycloaddition of phenyl azide to the corresponding alkyne. The latter was obtained via a Corey–Fuchs reaction sequence from the previously reported formyl derivative. As the proof of concept for their potential in MOF design, one of the nitriles was used to build an Ag-based network.

Direct exfoliation of layered zeolites into solutions of monolayers has remained unresolved since the 1990s. Recently, zeolite MCM-56 with the MWW topology (layers denoted mww) has been exfoliated directly in high yield by soft-chemical treatment with tetrabutylammonium hydroxide (TBAOH). This has enabled preparation of zeolite-based hierarchical materials and intimate composites with other active species that are unimaginable via the conventional solid-state routes. The extension to other frameworks, which provides broader benefits, diversified activity, and functionality, is not routine and requires finding suitable synthesis formulations, viz. compositions and conditions, of the layered zeolites themselves. This article reports exfoliation and characterization of layers with ferrierite-related structure, denoted bifer, having rectangular lattice constants like those of the FER and CDO zeolites, and thickness of approximately 2 nm, which is twice that of the so-called fer layer. Several techniques were combined to prove the exfoliation, supported by simulations: AFM; in-plane, in situ, and powder X-ray diffraction; TEM; and SAED. The results confirmed (i) the structure and crystallinity of the layers without unequivocal differentiation between the FER and CDO topologies and (ii) uniform thickness in solution (monodispersity), ruling out significant multilayered particles and other impurities. The bifer layers are zeolitic with Bronsted acid sites, demonstrated catalytic activity in the alkylation of mesitylene with benzyl alcohol, and intralayer pores visible in TEM. The practical benefits are demonstrated by the preparation of unprecedented intimately mixed zeolite composites with the mww, with activity greater than the sum of the components despite high content of inert silica as pillars.

Secondary electrospray ionization coupled with high resolution mass spectrometry (SESI-HRMS) is a direct mass spectrometry technique, which can identify trace volatile organic compounds (VOCs) in real time without sample pretreatment and chromatographic separation. SESI-HRMS has been successfully applied in multiple applications, including breath analysis, animals and plants VOCs emissions, analysis of headspace of cell cultures and indoor and outdoor air. The range of areas where the technique can potentially have a substantial impact is very broad. However, one critical aspect that requires further development to consolidate the technique is absolute quantification. Therefore, in this study we aim to develop a quantitative method for eight representative VOCs, including ketones (acetone, 2-butanone and 2-pentanone), alkenes (isoprene and α-terpinene) and aromatics (toluene, styrene and mesitylene). The mass spectrometric platform includes a commercial SESI source hyphenated with a Q-Exactive hybrid quadrupole Orbitrap high resolution mass spectrometer. Within the concentration range of 0–100 ppbv studied, the optimal coefficient of determination for linear regression (R2 = 0.993–0.999) between signal intensity and concentration is obtained in the range of 0–10 ppbv for all eight VOCs. The detection limits range between 3 (2-Pentanone) and 15 (Acetone) pptv. The intra-day (n = 10) and inter-day (n = 30) coefficients of variation (CV) are ≤ 6% and ≤10%, respectively. Finally the method is applied for the fast evaluation (

Diltiazem, which is a calcium channel blocker, is involved in the formation of covalent organic frameworks (COFs) through the Schiff base reaction of tetrakis (4-aminophenyl)-porphine (TAPP) and dihydroxynaphthalene-dicarbaldehyde (DHNDC) and the next enol-to-keto tautomerization. The diltiazem-imprinted COFs (DICOFs) were optimally formed using Sc(OTf)3 as the catalyst, TAPP/DHNDC/diltiazem in a molar ratio of 2/3/4, N-methylpyrrolidone/mesitylene (v/v = 3/5) as the porogen, and a 1-h reaction with a high imprinting factor of 10.5 compared to the nonimprinted counterparts (NICOFs). The optimized DICOF exhibited a more amorphous XRD pattern, a larger surface area (1650 vs. 930 m2/g), a larger pore volume (1.33 vs. 0.75 cm3/g), and a finer porous SEM feature than NICOF. The selectivity of NICOF toward diltiazem and diazepam at 250 nM (α = 1.03, RSD = 1.3%) was smaller than the selectivity of DICOF (α = 2.94, RSD = 1.6%). The diltiazem samples (5.0–300 ng mL−1) dynamically quenched the fluorescence of 15 μg/mL DICOF in 50 mM phosphate buffer at pH 6.5 at 8.0 min equilibrium; thus, Stern−Volmer plots were linearly constructed for sensing diltiazem with an LOD of 3.4 ng mL−1 and an LOQ of 10.2 ng mL−1. According to the plots, 30 ng mL−1 diltiazem solutions that were diluted from 30 mg-specified tablets had an average measured concentration of 29.5 ng mL−1 (σ = 1.3% and n = 5). In addition to application as fluorescent sensors, DICOFs (30 mg) could be used as dispersive extractants to recover 95.2% of 0.6 ng mL−1 diltiazem from 25 mL phosphate buffer with quadruplicate uses of 0.5 mL methanol/acetic acid (v/v = 9/1) as the eluent. Langmuir and pseudo-second-order models were fitted to the isothermal and kinetic sorption mechanisms, respectively. The maximum sorption capacity of DICOF was ten times larger than that of NICOF (156 vs. 15.2 mg/g). The interday recoveries of 0.6 ng mL−1 spiked in 20-fold diluted human urine, and 60-fold diluted human serum were 93.2% and 90.6%, respectively.

Timolol accompanied the formation of fluorescent β-ketoenamine-linked covalent organic frameworks (COFs) via the Sc(Tof)3-catalyzed condensation of derivated carbaldehyde and hydrazide in a 1,4-dioxane/mesitylene porogen to construct timolol-imprinted COFs (TICOFs). With high imprinting factors, the synthesis-optimized TICOFs were characterized by fluorescence, UV-Vis spectrometry, X-ray diffraction, N2 adsorption/desorption analyses, scanning electron microscopy, and FTIR spectrometry. The TICOF fluorescence measured at 390 nm/510 nm is dynamically quenched by timolol and was thus utilized to quantify timolol in a linear range of 25–500 nM with a LOD of 8 nM. The TICOF recovered 99.4% of 0.5% timolol maleate in a commercial eye drop (RSD = 1.1%, n = 5). In addition, TICOF was used as a dispersive sorbent to recover 95% of 2.0 nM timolol from 20 mg of TICOF in 25 mL phosphate buffer. Dilution factors of 25 and 75 were the maximum tolerated proportions of the urine and serum matrix spiked with 2.0 nM timolol to reach recoveries of 92.4% and 90.3%, respectively.

Mixing the liquids hexafluorobenzene (1) and 1,3,5-trimethylbenzene (mesitylene, 2) results in a crystalline solid with a melting point of 34 °C. The solid consists of alternating π−π stacked pillars of both aromatics. This simple experiment can be used to visually demonstrate the existence and the effect of noncovalent intermolecular π−π stacking interactions. Both benzene derivatives are relatively benign and widely available, and the experiment can be performed within minutes for less than $15 when done on a 22 mL scale (total volume). The demonstration is very robust, as 1:2 mixtures in volume ratios between 2/3 and 3/2 all give a visually similar result (molar ratios of 1.8−0.8). Substituting 2 with the liquid aromatics o-xylene, p-xylene, and aniline also resulted in the formation of a crystalline solid, while using many other liquid aromatics did not.

MWW type zeolites are characterized by the presence of zeolitic layers of 2.5 nm thickness, containing 10-member ring sinusoidal channels inside and supercavities with 12-member ring openings located on their surfaces. Expansion and pillaring of layered zeolites increase the access to active sites and can enable or facilitate catalytic activity towards larger reactant molecules. This goal is explored in this work reporting the pillaring of layered zeolite MCM-56 with MWW topology by tetraethylorthosilicate (TEOS) treatment with the assistance of isopropanol, aimed at obtaining hierarchical micro-mesoporous systems. MCM-56 (Si/Al = 12) was synthesized with hexamethyleneimine as a structure-directing and aniline as a structure-promoting agent. Hierarchical porous systems were obtained using two different pillaring methods: (1) with TEOS only and (2) with TEOS mixed with isopropanol. The MWW framework was preserved during swelling/pillaring in both methods. Pillared zeolites obtained via alcohol-assisted pillaring possessed unique intermediate micro-mesopores with the size of about 2 nm. IR study revealed a decrease in the concentration of accessible acid centers upon pillaring. However, the fraction of acid sites on the external surface, accessible for adsorption of large molecules, increased by up to 90%. Catalytic activity was evaluated in the Friedel-Crafts alkylation of mesitylene with benzyl alcohol. Pillaring resulted in reduction of the acid site concentrations, but the materials retained high catalytic activity. Pillaring in the presence of alcohol produced increased turnover frequency values based on the concentrations of the external acid sites.

Zeolite belongs to one of the most important families of solid acid catalysts in chemical industries. It is, however, severely constrained by the diffusion limitation for bulky molecules, a lack of multifunctionality for sequential reactions and pore adaptability toward specific adsorbates due to its small micropore size and simple aluminosilicate framework. Introducing mesopores into a zeolite toward realizing hierarchical zeolites is a prevailing strategy but one that usually suffers from compromised crystallinity as well as insufficient interconnectivity and openness of the mesopores. Herein, a novel acid-redox co-functionalized single-crystalline zeolite with highly open and interconnected mesopores is designed and fabricated. As a proof-of-concept study, we integrate solid acid and Fe-oxy redox sites into a hierarchical MEL zeolite with well-characterized microporosity and mesoporosity. This zeolite exhibits superior activity and stability toward alkylation between mesitylene with benzyl alcohol, arising from greatly facilitated intra-crystal molecular diffusion, mitigated metal leaching and optimized adsorbate-pore wall interactions.

We acknowledge the financial support from the Spanish Ministry of Science and Innovation (CTQ2017-89443-C3-2-R and PDC2021-120835-C21) and the regional Government of the Principality of Asturias (IDI/2018/000116).

Re/Pd-TiO2/SiO2 and Co/Mo-Al2O3/SiO2 aerogel catalysts were synthesized using sol-gel method and supercritical drying in excess solvent, and investigated in the hydrodesulphurisation (HDS) of dibenzothiophene (DBT) and 4,6-dimethyl dibenzothiophene (4,6-DMDBT). The influence of supercritical drying on the final catalytic properties of the materials was determined by parallel synthesis of aerogels and xerogels for Re/Pd-TiO2/SiO2 catalysts. The sol-gel method and supercritical drying were found to result in amorphous aerogels with relatively high degree of uniformity, of both supports and active phases. Corresponding xerogels were found to be similar to aerogels in terms of composition and structure, but characterized by lower specific surface areas. Catalytic activity of Co/Mo-Al2O3/SiO2 aerogel catalysts in HDS of DBT and 4,6-DMDBT has shown no major improvement in comparison to conventional Co/Mo catalyst. On the other hand, Re/Pd-TiO2/SiO2 aerogels, obtained with the addition of mesitylene or without it, achieved 70 % and 64 % higher conversion of 4,6-DMDBT than conventional Co/Mo catalyst, respectively. Increased catalytic activity can be attributed to well dispersed Re and Pd active phases across the catalyst structure, good incorporation of Ti within silica matrix, increased mesopore volumes and high specific surface areas.

A simple kinetic model based on the zeolite acid strength, the number of Brønsted acid sites, and the catalyst efficiency was developed for the cracking of n-hexane. A series of HY zeolites with a mesopore volume from 0.04 to 0.32 cm3/g was synthesized and characterized by various physical-chemical methods and tested for n-hexane cracking. The generation of mesoporosity influenced several other important parameters, such as acidity and extra-framework aluminum. Zero-length column diffusion measurements for mesitylene showed a large decrease in the characteristic diffusion time upon the introduction of mesoporosity, which changed only slightly with a further increase in mesoporosity. Similar n-hexane physisorption enthalpies were measured for all samples. The highest initial activity for n-hexane cracking per catalyst volume was observed for the sample with an intermediate mesopore volume of 0.15 cm3/g. The three mesoporous H-USY zeolites showed the same value of the intrinsic rate constant and the same activation energy. The difference in initial activity of the mesoporous zeolites was caused by the difference in the number of Brønsted acid sites. The increase in initial activity for the mesoporous zeolites compared to a microporous zeolite was caused by an increase in the acid strength.

In this study, the preparation of some large-pore ordered mesoporous silicas using a proper surfactant with different swelling agents was carried out. The synthesis of conventional SBA-15 was modified to obtain pore-expanded materials, with pore diameters up to 10 nm. To use a micelle swelling agent with a moderate swelling ability, three swelling agents were selected: 1-phenyl-decane (Dec), butyl benzene (BB), and mesitylene (Mes). These syntheses aimed to achieve a pore diameter enlargement but at the same time to avoid the formation of heterogeneous and/or poorly defined nanostructure of silica. The CO2 adsorbents were obtained by post-synthesis functionalization treatments carried out by grafting with 3-aminopropyl triethoxysilane. The CO2 adsorption/desorption experiments showed that carbon dioxide sorption capacities depend on the textural characteristics and the temperature used for the adsorption process. Good CO2 adsorption capacities were obtained for all prepared adsorbents, especially for SSBA-15-Mes-sil and SSBA-15-BB-sil samples. At 50 °C, the SSBA-15-Mes-sil sample has an adsorption capacity of 3.58 mmol CO2/g SiO2, and an efficiency of amino groups of 0.99 mmol CO2/mmol NH2. The results of adsorption capacities are comparable or even superior with the ones reported in literature for mesoporous silica functionalized with different amines. After nine adsorption–desorption cycles, the performance of the SSBA-15-Mes-sil adsorbent is relatively stable, with a low decrease in the adsorption capacity (0.1 mmol/g of CO2, i.e., 2.8% of initial capacity). These studies show the potential of mesoporous silica for carbon dioxide capture.

Cluster growth reactions in the system [Cu5](Mes)5 + [Al4](Cp*)4 (Mes = mesitylene, Cp* = pentamethylcyclopentadiene) were explored and monitored by in situ LIFDI-MS and 1H-NMR. Feedback into experimental design allowed for an informed choice and precise adjustment of reaction conditions and led to isolation of the intermetallic cluster [Cu4Al4](Cp*)5(Mes) (1). Cluster 1 reacts with excess 3-hexyne to yield the triangular cluster [Cu2Al](Cp*)3 (2). The two embryonic [Cu4Al4](Cp*)5(Mes) and [Cu2Al](Cp*)3 clusters 1 and 2, respectively, were shown to be intermediates in the formation of an inseparable composite of the closely related clusters [Cu7Al6](Cp*)6 (3), [HCu7Al6](Cp*)6 (3H) and [Cu8Al6](Cp*)6 (4), which just differ by one Cu core atom. The radical nature of the open-shell superatomic [Cu7Al6](Cp*)6 cluster 3 is reflected in its reactivity towards addition of one Cu core atom leading to the closed shell superatom [Cu8Al6](Cp*)6 (4), and as well by its ability to undergo σ(C–H) and σ(Si–H) activation reactions of C6H5CH3 (toluene) and (TMS)3SiH (TMS = tris(trimethylsilyl))., Cu/Al cluster growth reactions leading to open- and closed-shell superatoms are investigated. Therein, LIFDI-MS is presented as a powerful technique for the in situ detection of cluster identities and reactivity patterns.