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While the formation and breaking of transition metal (TM)-carbon bonds plays a pivotal role in the catalysis of organic compounds, the reactivity of inorganometallic species, that is, those involving the transition metal (TM)-metalloid (E) bond, is of key importance in most conversions of metalloid derivatives catalyzed by TM complexes. This Review presents the background of inorganometallic catalysis and its development over the last 15 years. The results of mechanistic studies presented in the Review are related to the occurrence of TM-E and TM-H compounds as reactive intermediates in the catalytic transformations of selected metalloids (E = B, Si, Ge, Sn, As, Sb, or Te). The Review illustrates the significance of inorganometallics in catalysis of the following processes: addition of metalloid-hydrogen and metalloid-metalloid bonds to unsaturated compounds; activation and functionalization of C-H bonds and C-X bonds with hydrometalloids and bismetalloids; activation and functionalization of C-H bonds with vinylmetalloids, metalloid halides, and sulfonates; and dehydrocoupling of hydrometalloids. This first Review on inorganometallic catalysis sums up the developments in the catalytic methods for the synthesis of organometalloid compounds and their applications in advanced organic synthesis as a part of tandem reactions.

The paper presents preliminary application studies of the innovative TiO2-SiO2/ POSS filler as a potential low-density polyethylene modifier. It was found that the addition of the filler increases the stiffness and hardness of the composite and slightly changes the intensity of its color.

The presented work is a continuation of research on the reactivity of unsaturated borasilsesquioxanes under the conditions of common organometallic transformations. The catalytic hydrosilylation reaction with silanes, siloxanes and silsesquioxanes in presence of platinum catalyst was explored. The majority of the products were obtained in high yields (90 %) and their structures were confirmed and characterized by spectroscopy and spectrometry, i. e. NMR and MALDI-TOF-MS. The most significant segment of the work is research on the spontaneous redistribution reaction of the alkoxy group from silane to borane moiety occurring in the obtained products, not being limited to the heterosilsesquioxane chemistry, however. The products were confirmed using GC-MS, ESI-MS methods and B3LYP exchange-correlation, in order to ascertain formation of the silicon-boron hybrid molecule.

A new polyhedral oligomeric silsesquioxane (POSS) methacrylate monomer, 1-(3-(methacryloyloxy)propyl)dimethylsiloxy-3,5,7,9,11,13,15-hepta(isobutyl)pentacyclo-[9.5.1.13,9.15,15.17,13]octasiloxane ((i-Bu)7POSS-OSiMe2-MA, 1), with a flexible spacer between the cubic POSS cage and methacrylate group was synthesized to reduce steric strain and thus achieve polymethacrylates (poly(POSS-MA)s) with high molecular weight (MW). Atom transfer radical polymerization (ATRP) of 1 at high monomer concentration (1 M, corresponding to ca. 85 wt % of 1) led to polymers with the absolute number-average MW, determined by multiangle laser light scattering, Mn,MALLS = 2 350 000 (and apparent MW, measured by gel permeation chromatography with linear poly(methyl methacrylate) (PMMA) standards, Mn,GPC = 550 000). Optimization of the reaction conditions, including the ATRP catalyst, targeted degrees of polymerization, monomer concentrations, as well as a monomer feeding, resulting in the first well-defined high MW polymers with P...

Herein, we report an efficient synthesis and functionalization of trifunctional open-cage-type silsesquioxanes. The method proposed has been successfully applied for the synthesis of a library of incompletely condensed silsesquioxanes with vinyldiorganosilyl functional groups, which allows further modification. Detailed studies of hydrosilylation of sterically different open-cage vinylsilsesquioxanes with a wide spectrum of phenylsilanes catalyzed by platinum and rhodium compounds are also reported. The influence of the reaction parameters, types of reagents, and catalysts employed on the efficiency of the process was examined. Optimization of the process based on the above results permitted the design of a very attractive method for the synthesis of multifunctionalized silsesquioxanes with excellent yields and regioselectivity. Moreover, the results allowed the choice of the most efficient catalyst whose application led to the selective formation of substituted open-cage silsesquioxanes. These new compounds have been fully characterized and studied in terms of their thermal properties., The first example of a fully specified synthetic protocol allowing selective modification of trivinyl-substituted open-cage silsesquioxanes with silanes via platinum-catalyzed hydrosilylation is presented.

Herein we present a simple catalytic approach to the synthesis of organosilylfunctional polybutadienes. The use of highly active Rh(I) catalysts enabled high conversions of a wide range of organofunctional silicon-based modifiers, which permitted obtaining a library of new functional polymers equipped with attractive silicon-based functional groups. The use of real-time FT-IR spectroscopy allowed us to determine the end-point of the reaction as well as the influence of steric and electronic properties of functional groups on the course of hydrosilylation. In addition, it allowed us to establish the impact of the spacers between a H–Si≡ moiety and the functional group on the reactivity of the synthesized silanes or siloxanes in the polybutadiene hydrosilylation reactions. All products were characterized by NMR spectroscopy and GPC analysis.

We have developed a new effective route for obtaining (E)-vinyl-substituted silatranes via ruthenium-catalyzed silylative coupling of 1-allylsilatrane with olefins. Experimental research allowed us also to propose the mechanism of the process based on stoichiometric reactions.

A facile and efficient Pd-based Suzuki–Miyaura coupling reaction leading to mixed chromophores with styryl fragments, enabling their further application, is presented. We also disclose their use in the formation of monofunctionalized silsesquioxanes with a chromophore group covalently bound to a T8 core that have been prepared via a cross-metathesis reaction. These new materials were studied in terms of their photophysical and also thermal properties.

The functionalization of mono- and octahydrospherosilicate with vinylboranes and allylboranes via hydrosilylation reaction in the presence of a Karstedt’s platinum (0) catalyst is presented. This is the catalytic route to obtain a new class of silsesquioxanes containing boron atoms in their structure in high yields (&gt, 90%) and with satisfactory selectivity. The obtained compounds were fully characterized by spectroscopic (1H, 13C, 29Si NMR) and spectrometric methods (MALDI-TOF-MS), as well as thermal analysis (TGA). The obtained compounds were subjected to thermal tests, characterizing the processes of melting, thermal evaporation, sublimation and thermal decomposition.

In this paper, the effective functionalization of silsesquioxane (HSiMe2O)8Si8O12 (1) via hydrosilylation of two different functional alkenes is presented. For the first time, such a wide spectrum of statistically bifunctional silsesquioxanes (RSiMe2O)∼4(R′SiMe2O)∼4Si8O12 was obtained and characterized. Seventeen new systems with various substituents (Si–H, hydroxyl, ester, epoxy, alkenyl, or alkyl) were prepared by two synthetic approaches. The first method was based on the subsequent hydrosilylation of two alkenes in a one-pot manner, whereas the second one consisted of a two-step protocol in which intermediates (RSiMe2O)∼4(HSiMe2O)∼4Si8O12 were isolated and then reacted with the second alkene, in the presence of the same or a different catalyst. Resulting systems due to the presence of two various groups attached to the silsesquioxane cage can be considered as potential cores for the synthesis of (hyper)branched molecules or macromolecules.

Herein we present the results of our studies on the hydrosilylation of polybutadiene with alkyl, aryl and alkoxysilanes in the presence of platinum and rhodium complexes. In order to select the most efficient catalytic system, which, under optimal conditions, would smoothly promote incorporation of the above-mentioned organosilicon modifiers into polybutadienes of various structures via hydrosilylation, the real-time in-situ FT-IR spectroscopy was used. The silyl-functionalized polymeric products were characterized by NMR analysis and gel permeation chromatography (GPC). It was demonstrated that the stereo-electronic properties of substituents directly bonded to the HSi moiety play a crucial role in formation of desired products, as well as affect the time required for total conversion of organosilicon reagents. Partially modified polymers containing pendant alkoxy groups can be applied as additives to rubber compounds to enhance dispersion of inorganic particles in the polymer matrix, as well as to promote formation of organic-inorganic hybrid materials.

In this paper, an efficient method for the preparation of new silsesquioxanes with mixed functional groups of general formula (RSiMe2O)n(ViSiMe2O)8−nSi8O12 is described. The proposed protocols are based on hydrosilylation of octakis(dimethylvinylsiloxy)octasilsesquioxane ((ViSiMe2O)8Si8O12) with unsymmetrical disiloxanes. As an example of possible modification of (RSiMe2O)n(ViSiMe2O)8−nSi8O12 derivatives, a thiol addition was distinguished. A series of silsesquioxane compounds with a variety of functional groups (silylamine, epoxy, and chlorine) were obtained and characterized. The obtained compounds can be considered as novel multi-substituted materials, which significantly increase the possibility of the synthesis and design of new functional materials.

The first report of using limonene derivative of a spherosilicate as a modifier of polylactide used for 3D printing and injection moulding is presented. The paper presents the use of limonene-functionalized spherosilicate derivative as a functional additive. The study compared the material characteristics of polylactide modified with SS-Limonene (0.25&ndash, 5.0% w/w) processed with traditional injection moulding and 3D printing (FFF, FDM). A significant improvement in the processing properties concerning rheology, inter-layer adhesion, and mechanical properties was achieved, which translated into the quality of the print and reduction of waste production. Moreover, the paper describes the elementary stages of thermal transformations of the obtained hybrid systems.

Two phosphorus-containing cage-like silsesquioxane derivatives were synthesized as reactive or additive flame retardants for epoxy resin. The silsesquioxanes were obtained via an epoxide ring-opening reaction using a 10-hydroxy-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPA). In one derivative containing in its structure 4 glycidoxypropyl and 4 phosphate groups, denoted as 4P4GS, only half of the epoxy rings was reacted with phosphate to obtain a reactive additive, while in the second derivative containing 8 phosphate groups, denoted as 8PS, all epoxy groups were converted, thus an additive modifier was obtained. The silsesquioxanes containing phosphorus atoms and the reactive phosphorus-free silsesquioxane derivative (octakis[(3-glycidoxypropyl)dimethylsiloxy]octasilsesquioxane (8GS)) were used to prepare hybrid materials based on epoxy resin. To compare the impact of the structure of silsesquioxane derivatives on the properties of hybrid materials, a number of samples containing 1, 5, and 10% of the modifiers making a series of epoxy materials containing additive or reactive modifiers, were obtained. The modified epoxies were studied using scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDS), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), nanoindentation, water contact angle, and cone calorimetry tests to assess the effects of the modifier structure on the physicochemical properties of the investigated materials.

Bifunctional silsesquioxanes create an attractive group of compounds with a wide range of potential applications, and recently they have gained much interest. They are known to be obtained mainly via hydrosilylation, but we disclose novel synthetic protocols based on different but complementary reactions, i.e., cross-metathesis (CM) and silylative coupling (SC). A series of cubic T8 type silsesquioxane derivatives with a broad scope of styryl substituents were synthesized in a one-pot procedure and characterized by spectroscopic and spectrometric methods. All of the new compounds can be obtained in a one-pot manner, which has an attractive impact on the synthetic procedure, as it is economic in terms of the isolation of intermediate products. Additionally, the methodology disclosed here enables the (E)-stereoselective introduction of styrenes derivative to the cubic T8 type core. The presented compounds can be interesting precursors for a further functionalization that may significantly increase the possibility of their application in the design and synthesis of new functional materials.

In this work, we present the first example of highly efficient platinum-catalyzed hydrosilylation of vinyl- and allylgermanes with different types of silsesquioxanes and spherosilicates. This protocol allows the straightforward introduction of organogermyl functionalities with alkyl chains linked to the silsesquioxane core with good yields and excellent selectivity. These derivatives may be applied as precursors for the development of advanced hybrid materials in the future. In addition, a comparison made between vinylsilanes and vinylgermanes showed a higher reactivity of germanium compounds in the hydrosilylation reaction. To the best of our knowledge, this is the first literature example of the functionalization of silsesquioxanes and spherosilicates with these types of germanium derivatives. The reaction parameters and kinetics were determined by in situ FT-IR. In addition, our research is supported by extensive data obtained from NMR measurements.

Herein we report a study of highly efficient platinum-catalyzed hydrosilylation of dialkenylgermanes with silsesquioxanes and spherosilicates. The use of divinyl- and diallylgermanes allowed the synthesis of new classes of compounds, i. e., dumbbell-type systems, silsesquioxanes with alkenyl pendant group, and oligomeric derivatives. The results are supported by detailed data from in situ FT-IR and NMR measurements, enabling precise monitoring of the reaction progress and determination of regioselectivity of the formed products.

This paper reports on detailed studies on the hydrosilylation of alkenes and alkynes with silsesquioxane (HSiMe2O)(i-Bu)7Si8O12, catalyzed by Pt, supported on a styrene-divinylbenzene copolymer (Pt/SDB). The obtained results clearly indicate that Pt/SDB was a very efficient catalyst, characterized by high TON in the hydrosilylation of a wide spectrum of reagents. The heterogeneous character of the catalyst permitted reuse up to 20 times. The selectivity of all the hydrosilylation reactions was very high, regardless of the catalyst concentration. Pt/SDB is the first example of a heterogeneous catalyst being used for the functionalization of silsesquioxane (HSiMe2O)(i-Bu)7Si8O12. Under the tested conditions it was found to be more effective than commercially available and industrially applied Pt catalysts supported on activated carbon, making it one of the most versatile and potentially interesting heterogeneous systems in hydrosilylation reactions.

In this paper, we propose an efficient method for the synthesis of new organosilicon compounds based on hydrosilylation of functional olefins with monohydrido POSS as well as hydrosilylation of monovinyl POSS with functionalized monohydrodisiloxanes. A large number of new compounds were obtained and comprehensively characterized. These compounds can be building blocks for the synthesis of novel hybrid molecules and macromolecules.

The effect of the addition of octakis(tetramethylammonium)-t8-silsesquioxane (octaanion) on the modification of the porous structure of the silica gel obtained by the sol-gel method catalysed by acetic acid was studied. The obtained silica gel was characterised by the low-temperature nitrogen adsorption/desorption method (BET), powder diffraction (XRD), thermogravimetry (TG) and microscopic observations (TEM). The octaanion was found to act as a textural promoter, as evidenced by almost a 25% increase in the surface area of the obtained silica. As a result of the stabilisation in the porous structure of the silica gel, the tetramethylammonium groups of the octaanion show higher thermal stability than the groups present in the octaanion structure or those introduced in the form of tetramethylammonium hydroxide. Tetramethylammonium ions were proved to show increased thermal resistance, which is related to the porous properties of the SiO₂ matrix.

An effective and selective approach for the synthesis of new organofunctional triallyl isocyanurate derivatives, via hydrosilylation reaction with silanes and siloxanes bearing attractive functional groups, is reported. The presence of Pt-Karstedt's complex led to the total conversion of reagents, as well as, the formation of β-regioisomeric products. The new compounds are valuable building blocks for the synthesis of a variety of hybrid materials, were characterized by FT-IR, 1H, 13C and 29Si NMR spectroscopy.

Poly(trimethylene terephthalate–block–tetramethylene oxide) (PTT–PTMO)/polyhedral oligomeric silsesquioxane (POSS) nanocomposites, synthesized by in situ polymerization, are characterized in detail in terms of interfacial interactions between functional groups on the surface of POSS and polymer chains. The impact of POSS incorporation on the molecular mobility is investigated by means of dielectric spectroscopy. It is found that PTT–PTMO/POSS nanocomposites exhibit higher values of stress at strain of 100% that in comparison with neat PTT–PTMO might result from the influence of POSS particles on the molecular mobility of polymer chains, which is probably due to the interfacial interactions between functional groups on the surface of POSS particles with the polymer matrix. Moreover, it is found that there is no variation of the segmental relaxation for the nanocomposite investigated and there is an increase in the interfacial polarization induced by the presence of POSS as seen in the increment of the real part of the dielectric permittivity.

In this paper we demonstrate a facile and efficient synthesis of monoalkenylsubstituted POSS compounds, i.e., R7(Si8O12)-alkenyl and R7(Si8O12)(OSiMe2)-alkenyl with a functional alkenyl group of chain length (from vinyl to dec-9-enyl, with or without additional –OSiMe2– spacer between the silsesquioxane core and alkenyl moiety) and with five types of inert groups (Et, iBu, iOc, Cy, Ph) at the POSS core. These compounds constitute a library of monosubstituted POSS systems, including thorough spectroscopic and thermal characteristics. These findings could be especially useful for material chemists applying the compounds as modifiers or comonomers for copolymerization reaction, e.g., with olefins.

The synthesis and characterization of two biphenyl phosphates of different structures, as substrates for preparation of two series of functionalized addition silicone rubbers of different crosslink density and amount of pendant functional groups, is presented. Obtained materials were applied as flame retardant protective coatings for cotton fabric and characterized by TG and MMC techniques. The relationship between thermal stability, flame-retardant properties, and structure of prepared silicone rubbers is discussed.

An effective approach for the syntheses of new di- and hexafunctional cyclotriphosphazenes, based on olefin or silylacetylene hydrosilylation with 4-dimethylsilylphenoxy cyclotriphosphazene derivatives, is reported. All new compounds obtained with high yields and selectivities were isolated and characterized by 1H, 13C, 29Si, 31P NMR and FT-IR techniques.

The copolymers of ethylene with the double-decker silsesquioxane (DDSQ) were synthesized by copolymerization with the use of metallocene and bis(phenoxy-imine) catalysts. The influence of the kind of the catalyst and polyreaction conditions on the performance of copolymerization as well as on the properties of the copolymers was studied. Depending on polyreaction parameters, the DDSQ contents in the copolymer varied in the range of 0.93–11.53 wt% which determined the compositions and the structural properties of copolymers. DDSQ incorporated into the polymer chain could constitute pendant groups in the main chain or it could act as a cross-linking agent. The ethylene/DDSQ copolymers also had different kinds and contents of unsaturated end groups and they offered interesting morphological and thermal properties including various glass transition temperatures as well as melting and crystallization behaviours.

Ruthenium-N-heterocyclic carbene complexes with the generic formula [RuHCl(CO)(NHC)(PCy3)] exhibit a high catalytic activity toward the (E)-selective silylative coupling of divinyl-substituted double-decker silsesquioxanes with two distinctly substituted styrenes. This process leads to a novel class of unsymmetrically functionalized silsesquioxane derivatives.

The research presented in this work comprehensively describes hydrosilylation of a wide spectrum of alkenes which contain one or more reactive groups with (HSiMe2 O)(iBu)7 Si8 O12 , in the presence of different types of catalysts. Special attention is paid to the influence of alkene, catalyst, and reaction conditions on process effectiveness and selectivity by the precise monitoring of the experiments with in situ FTIR and NMR spectroscopies. More than twenty silsesquioxanes bearing reactive groups (OH, Br, NR2 , CO, COOR, NCO, epoxy, SiR3 ) commonly used in organic and polymer chemistry, were obtained, isolated and characterized by 1 H, 13 C, 29 Si NMR and MALDI TOF. Importantly, in the presented syntheses, commercially available reagents and catalysts were used, meaning that the presented methods could be easily repeated, rapidly scaled up, and widely applied.

The routes of synthesis, as well as, spectroscopic and X-ray diffraction characterization of a new group of bis- or hexakis-4-(dimethyl(vinyl)silyl)phenoxy and 4-(dimethylsilyl)phenoxy-substituted cyclotriphosphazenes as a versatile starting substrates for the synthesis of a variety of organic cyclophosphazene derivatives, via catalytic hydrosilylation or silylative coupling processes, is presented.