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Silicon-stereogenic chiral organosilanes have found increasing applications in synthetic chemistry, medicinal chemistry, and materials science. In this context, various asymmetric catalytic methods have been established for the diverse synthesis of silicon-stereogenic silanes. In particular, asymmetric organocatalysis is emerging as an important and complementary synthetic tool for the enantioselective construction of silicon-stereocenters, along with the rapid development of chiral-metal catalyzed protocols. Its advent provides a powerful platform to achieve functionalized silicon-stereogenic organosilanes with structural diversity, and should lead to great development in chiral organosilicon chemistry. In this Tutorial Review, we highlight these latest achievements from two aspects: desymmetrizations of prochiral tetraorganosilanes and dynamic kinetic asymmetric transformations of racemic organosilanes by employing five organocatalytic activation modes. The advantages, limitations and synthetic value of each protocol, as well as the synthetic opportunities still open for further exploration, are also discussed. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: By rational modification of electronic and steric properties of pincer ligands, a Co/Fe dual catalyst system is developed for one‐pot sequential Markovnikov alkyne hydrosilylation and stereoselective alkene isomerization. The protocol provides an atom‐economical and efficient approach to trisubstituted (E)‐alkenyl silanes from widely accessible terminal alkynes with high regio‐ and stereoselectivities under mild conditions. The utility of this reaction was demonstrated by gram‐scale synthesis and derivatization of bioactive molecules. The radical clock and trapping experiments indicated that radical pathway might be operative in the alkene isomerization step. [ABSTRACT FROM AUTHOR]

Cobalt complexes featuring triazine‐based PNP ligands have proven to be exceptionally active and chemoselective pre‐catalysts in facilitating the dehydrogenative coupling between silanes and amines, leading to the synthesis of diverse aminosilanes. Notably, even challenging substrates exhibited high reactivity. The catalyst's unique feature of avoiding coupling with tertiary silanes enhances process chemoselectivity. It facilitates a more precise synthesis of silylamines possessing of SiH2−N and SiH−N motifs, overcoming challenges associated with broader reactivity seen in previous systems. In terms of its remarkable chemoselectivity, it is also noteworthy that the catalytic system exhibits both versatility and efficacy in converting substrates with untouched double and triple carbon‐carbon bonds. This accomplishment is particularly significant, given previous challenges brought about by the activity of commonly employed catalysts in the competitive hydrosilylation process. [ABSTRACT FROM AUTHOR]

Membrane technology has turned out to be a cornerstone in water treatment, providing advanced solutions that significantly enhance the efficiency of the purification process. The conventional reverse osmosis processes have shortcomings like large volume of rejects and fouling, which have been addressed largely using membrane distillation (MD). The ability of MD to treat a wide array of brines and hypersaline water sources, ranging from seawater to industrial wastewater, has made it a leading desalination technology. This review explores the role of silane chemistry in developing hydrophobic membranes, fundamental classification of silanes, grafting intricacies, critical pretreatment procedures, and techniques for silane functionalization. It further sheds light on the methods for evaluating hydrophobicity and performance metrics, highlighting the advantages of stable flux, enhanced solute rejection, and resistance to fouling. The paper particularly highlights the emergence of silanes as the preferred agents for enhancing membrane hydrophobicity that exhibit anti-wetting properties, concluding with a call for further research aimed at large-scale production of these membranes for global water treatment. [ABSTRACT FROM AUTHOR]

This study investigates the efficiency of already developed surface‐modified carbon black (CB), both independently and in conjunction with nano‐silica, as a hybrid filler, to the properties of natural rubber (NR) compounds. The modification process, followed by coupling agent treatment, enhanced cross‐link density and curing characteristics, though the inclusion of nano‐silica alone negatively affected curing due to its inherent polarity and tendency to agglomerate. The filled compounds with modified CB exhibited significant improvements in mechanical properties, notably tear resistance. Moreover, the combination of nano‐silica with modified CB yielded compounds with superior tear resistance, attributed to synergistic effects. CB surface modification exhibited varying effects on the glass transition temperature, with enhancements observed in tan δ at lower temperatures, indicating improved ice and wet grip potential. Also, it reduced rolling resistance after treatment with a coupling agent. While thermal stability remained consistent across the studied compounds, swelling resistance varies with filler type and ratio. Thermodynamic analysis confirmed the positive impact of CB surface modification on the elasticity and chain mobility of the investigated rubber compounds. It was concluded that the strategic selection of fillers and modification approaches were essential for achieving optimal results in the rubber compound's performance and application. [ABSTRACT FROM AUTHOR]

A strong and confined Brønsted acid catalyzed enantioselective cyclization of bis(methallyl)silanes provides enantioenriched Si-stereogenic silacycles. High enantioselectivities of up to 96.5:3.5 er were obtained for a range of bis(methallyl)silanes. NMR and ESI-MS studies reveal that the formation of a covalent adduct irreversibly inhibits turnover. Remarkably, we found that acetic acid as an additive promotes the collapse of this adduct, enabling full turnover. Experimental investigation and density functional theory (DFT) calculations were conducted to elucidate the origin of this phenomenon and the observed enantioselectivity. Among the diverse organosilicon compounds, Si-stereogenic silanes have recently demonstrated promising biological activities but only few protocols for the preparation of organosilicon compounds possessing a Si-stereogenic center exist in the literature. Here the authors show that a strong and confined Brønsted acid catalyzed enantioselective cyclization of bis(methallyl)silanes and provides enantioenriched Si-stereogenic silacycles. [ABSTRACT FROM AUTHOR]

Chromium is known to play an important role in various metabolic pathways; however, its excessive use can result in negative impact on mankind, this necessitates the development of sensors for Cr(III) ion. The current study has incorporated the synthesis of ether derived Schiff base allied silanes 4 a–4 d, which have been characterized using 1H NMR, 13C NMR and mass spectrometry. The spectroscopic technique of UV‐visible has been utilized to study the sensing behaviour of probe 4 a, resulting in a good sensing ability towards Cr(III) ion, yielding a detection limit of 4.2×10−7 M and an association constant value of 2.25×106 M−1. In order to study the stoichiometric binding between probe and metal ion, Job's plot method has been employed which shows 1 : 1 binding ratio. The mechanism of binding has been studied via 1H NMR, UV‐visible, FT‐IR spectroscopy and mass spectrometry. The binding has been further supported by DFT. The real sample analysis has been performed to validate the utility of the synthesized sensor in practical applications. The theoretical tool of molecular docking has been considered to study the protein‐ligand interaction between S. aureus bacterial protein and ligand 4 a, yielding a value of −7.63 kcal/mol for binding energy. [ABSTRACT FROM AUTHOR]

This article explores the development of a method for the asymmetric β-borylation of α,β-unsaturated acyl silanes using copper catalysis. The authors conducted experiments to optimize the reaction conditions and found that a ligand-free reaction produced the best results. They also investigated the range of the reaction and successfully synthesized various β-boryl acyl silanes with different substituents. The authors suggest that the inclusion of Li(acac) helps prevent undesired cleavage of the acyl silane moiety. Overall, this research provides valuable insights into the optimization and scope of a Cu I -catalyzed conjugate borylation reaction, which may have potential applications in further studies of bifunctional molecules. [Extracted from the article]

Ethylene dimerization is a significant process among the other petrochemical processes due to the production of alpha olefins as the most widely used industrial intermediate. Titanium tetra butoxide/tetrahydrofuran/ triethyl aluminum is the main homogeneous catalyst complex that has been used in this process. On the other hand, the formation of polymer or oligomerization side reactions are the salient obstacles in the ethylene dimerization process. The effect of various promoters from the group of halo hydrocarbons, along with different modifiers from the group of esters and silane compounds has been investigated to conquer the barriers mentioned above. The reaction conversion, selectivity, and polymer production are the remarkable parameters that have been evaluated to study the components’ impacts. The results indicated that the addition of promoters through reaction with triethyl aluminum (TEA) (co-catalyst) increased the reaction rate and thus augmented the conversion of the reaction to 88.26% and reduced the reaction time to 60 min. Among the promoters, the reaction conversion and selectivity of dichloromethane were, respectively, 88.26% and 78.45%, higher than that of dibromopropane (48.52% and 39.52%), but a higher amount of polymer was produced by dichloromethane. Moreover, esters strongly decreased the catalyst activity, resulting in a decrease in the conversion to under 25%. On the other hand, silanes showed a significant effect on the control of the polymer chains in Ziegler-Natta homogeneous catalysts. Dicyclopentyldimethoxysilane (DCPDS) modifier caused an increase of 1.5% in ethylene conversion and a 6% increase in the 1-butene selectivity. At the same time, the polymer formation also prevented a significant amount, so the amount of polymer decreased to about 2.1 mg. DCPDS modifier performed better than the cyclohexylmethyldimethoxysilane (CHMDS) donor. [ABSTRACT FROM AUTHOR]

The suitability of silanes H2N(C3H6)Si(OC2H5)3‐x(CH3)x (x=0, 1, 2) for the sealing of zeolite pores has been investigated. The sealing efficiency was evaluated by observing the exit kinetics of the fluorescent dye resorufin from the one‐dimensional main channels of zeolite L (ZL). The best results in terms of sealing quality were obtained with x=0, indicating the importance of ensuring maximum probability for siloxane bond formation and cross‐linking during the sealing process. The amino group thereby plays a crucial role in the positioning of the silane prior to covalent bond formation. Samples sealed with 3‐aminopropyltriethoxysilane (APTES) showed excellent stability against leaching in aqueous medium even under moderately alkaline conditions. Further evidence for the ability of APTES to efficiently seal the channels of ZL was obtained by nitrogen sorption measurements. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The asymmetric partial reduction of 1,3‐diketones stands as a straightforward pathway to access optically active β‐hydroxyketones. In this paper, an asymmetric Piers‐type hydrosilylation of 2,2‐difluoro‐1,3‐diketones was successfully realized by using a frustrated Lewis pair of chiral borane and tricyclohexylphosphine as a catalyst, delivering a variety of α,α‐difluoro‐β‐hydroxyketones in high yields with up to 99% ee. Significantly, no over‐reduced diol products were observed even with an excess amount of silanes. The product can be conveniently converted to α,α‐difluoro‐β‐hydroxyester or 1,3‐anti‐diol via an oxidation with m‐CPBA or a reduction with DIBAL‐H without obvious loss of ee. [ABSTRACT FROM AUTHOR]

The dispersion of a filler in a rubber matrix is a crucial parameter affecting the mechanical and dynamical properties of a rubber compound. It is the current issue of the rubber compounding industry because, most fillers are categorized as a mineral, while the rubber is an organic material. The surface modification of the filler has been accepted as an effective technique for the improvement of the abovementioned parameter. First, the surface premodification of commercial carbon black with a grade of N660 (CB) was implemented by four different oxidation methods. After that, among of used methods, the oxidation method using citric acid was selected to produce modified carbon black (CB‐Oxi) for further treatment. Subsequently, the coupling agent, Bis[3‐(triethoxysilyl)propyl] tetrasulfide (TESPT) was functionalized on the surface of CB‐Oxi to produce modified‐CB‐Oxi. Also, for comparison purposes, the TESPT functionalization was accomplished on untreated CB to form modified‐CB. The FTIR spectra of CB‐Oxi showed using the premodification method introduced the hydroxyl and carboxyl groups on the surface of CB. The correspondent spectra for modified‐CB‐Oxi confirmed the existence of silane groups on the surface of the carbon black. However, the mentioned silane groups were not observed on the surface of modified‐CB. The findings were strengthened by several characteristic techniques including, FESEM, XRD, EDS, CHNS elemental analysis, and RAMAN spectra. The FESEM graphs and elemental mapping showed homogeneous dispersion and uniform distribution of sulfur and silicon elements on the modified‐CB‐Oxi surface. According to RAMAN spectra, the disturbance in the structure of carbon black graphite was reduced after surface modification. modified‐CB‐Oxi is proposed as a potential substitute filler for current commercial carbon black in rubber compounding. [ABSTRACT FROM AUTHOR]

This study aimed to achieve enzyme mediated green synthesis of Zinc oxide nanoparticles and its antibacterial, antioxidant and anticancer activities using the leaf of Ipomea pes-caprae. The enzymes present in the leaf of Ipomea pescaprae were extracted and the extract obtained was subjected to GC-MS for the determination of bioactive compounds and thereby synthesized the zinc oxide nanoparticle using the extracted enzymes and studied their biological properties. The GCMS analysis of the I. pes-caprea leaf enzymes extract revealed the presence of 14 bioactive compounds with valuable biological activities. The major chemical constituents are n-Hexadecanoic acid, l-(+)-Ascorbic acid 2,6-dihexadecanoate, Tridecanoic acid, Methyl 8,11,14-heptadecatrienoate, 9,12,15-Octadecatrienoic acid, (Z,Z,Z)-, 2-Pyridinamine, N-(4,5-dihydro-5-methyl-2-thiazolyl)-3-methyl-,tert-Butyl(5-isopropyl-2methylphenoxy)dimethyl silane, 5-Acetamido-4,7-dioxo-4,7-dihydrobenzofurazan, Ethyl2-(2-chloroacetamido)-3,3,3-trifluoro-2-(4fluoroanilino) propionate, Benzo[h]quinoline, 2,4-dimethyl-, 1H-Indole, 1-methyl-2-phenyl-, 1,3-Benzodioxole, 5-(2-nitro-1-propenyl)-, Anthracene, 9,10-dihydro-9,9,10-trimethyl-. The enzymes extract supported the synthesis of zinc oxide nanoparticles and showed very good biological properties. The presence of various bioactive compounds in the enzyme-mediated synthesis of zinc oxide nanoparticles from the leaf of I. pes-caprea proved many medical importance. It can be concluded that the investigation has opened up an important perspective in pharmaceutical research and plant enzymes can be used for the development of potential, novel antioxidant and anticancer agents for the treatment of many diseases. [ABSTRACT FROM AUTHOR]

Copper‐catalyzed silylarylation of N‐(arylsulfonyl)acrylamides via a tandem silyl radical addition/1,4‐aryl migration/desulfonylation sequence has been developed. This method employs silanes as the precursor of silyl radical and di‐tert‐butyl peroxide (DTBP) as the initiator. By using this cascade procedure, a series of β‐silyl amide‐pharmaceutical hybrids which contain an α‐all‐carbon quaternary stereocenter were facilely synthesized. [ABSTRACT FROM AUTHOR]

X-ray photoelectron spectroscopy (XPS) and angle-resolved XPS (ARXPS) characterization of surface layers resulting from the functionalization of polymers such as polyvinylchloride (PVC) modified with 3(mercaptopropyl)-trimethoxysilane (MPTMS) and (3-aminopropyl) triethoxysilane (APTES) is challenging due to the overlap in signals, deriving both from the substrate and the functionalized layers. In this work, a freshly cleaved, ideally flat gold surface was used as carbon-free model substrate functionalized with MPTMS and subsequently grafted with APTES. Avoiding the overlap of signals from carbon atoms present in the substrate, the signals in the C1s, O1s, Si2p, S2p and N1s high-resolution spectra could be assigned to the MPTMS/APTES functionalized layer only and the curve-fitting parameters could be determined. Quantitative analysis was in very good agreement with the expected stoichiometry of the functionalized layer, confirming the adopted curve-fitting procedure. In addition, it was found that one molecule of APTES grafted two MPTMS via silane groups. ARXPS allowed for determining the thickness of the functionalized layers: MPTMS thickness was found to be 0.5 (0.2) nm, whereas MPTMS + APTES thickness 1.0 (0.2) nm was in good agreement with Avogadro model calculations. This approach can be considered a powerful tool for characterizing functionalized surfaces of more complex systems by XPS. [ABSTRACT FROM AUTHOR]

A cobalt‐catalyzed 1,2‐regioselective dicarbofunctionalization of silylated 1,3‐dienes with functionalized solid organozinc pivalates and alkyl bromides is disclosed, thus affording the alkylarylated and dialkylated silanes in a regioselective manifold. Herein, regioselectivity is steered by steric hindrance of the bulky silyl groups, which could prohibit the formation of the flexible π‐allylcobalt intermediate. Furthermore, derivatizations of the resulting products and modifications of bioactive molecules demonstrate the synthetical utility of our method. [ABSTRACT FROM AUTHOR]

Within the sphere of traditional Pd0/PdII cross coupling reactions, organogermanes have been historically outperformed both in terms of scope and reactivity by more conventional transmetalating reagents. Subsequently, this class of compounds has been largely underutilized as a coupling partner in bond‐forming strategies. Most recent studies, however, have shown that alternative modes of activation of these notoriously robust building blocks transform organogermanes into the most reactive site of the molecule—capable of outcompeting other functional groups (such as boronic acids, esters and silanes) for both C−C and C–heteroatom bond formation. As a result, over the past few years, the literature has increasingly featured methodologies that explore the potential of organogermanes as chemoselective and orthogonal coupling partners. Herein we highlight some of these recent advances in the field of organogermane chemistry both with respect to their synthesis and applications in synthetic and catalytic transformations. [ABSTRACT FROM AUTHOR]

Radical trifluoromethoxylation is an attractive approach to prepare compounds featuring the important OCF3 group, however most existing methods have focused on aromatic substrates. Here, we report novel methodologies with alkenyl substrates employing bis(trifluoromethyl)peroxide (BTMP) as a practical and comparatively atom economical trifluoromethoxylating reagent. With silyl enol ether substrates, switching reaction solvent allows for the synthesis of either α‐(trifluoromethoxy)ketone products or unprecedented alkenyl‐OCF3 species. Furthermore, allyl silanes have been employed as substrates for the first time, affording allyl(trifluoromethyl)ether products in good yields. In each case, the methods operate at room temperature without large excesses of the alkene substrate while, in contrast to previous radical trifluoromethoxylation reactions, no catalyst, light or other activators are required. [ABSTRACT FROM AUTHOR]

Europium‐doped yttrium oxide (Y2O3:Eu3+) is one of the main red‐emitting luminescent materials currently used in light‐emitting devices owing to its high luminous efficiency, high color purity, and other excellent optical characteristics. However, Y2O3:Eu3+ is hydrophilic, which is a major obstacle to its long‐term application in high‐humidity outdoor environments. Hydrophobic modification is a viable solution to this problem, and can give Y2O3:Eu3+ many excellent properties and functions, such as self‐cleaning ability, anti‐static performance, oil/water separation functions, and corrosion resistance. This study reports the preparation of hydrophobic Y2O3:Eu3+ particles modified with nonfluorinated alkyl silanes. Several influencing factors, including the length of the carbon chain in the silane coupling agent, the pH value of the reaction system, the reaction temperature, and the ratio of reactants, on the hydrophobicity of the prepared samples are studied in detail, and the optimal conditions are determined. A superhydrophobic Y2O3:Eu3+ material with a water contact angle of 151.6° is finally obtained. Moreover, FTIR, TG, SEM, XPS, XRD, and PL are used to explore the mechanism of the hydrophobic modification and the structural and fluorescence performance changes imparted by this modification. [ABSTRACT FROM AUTHOR]

Monocarbonyl rhodium complex LRh(CO), 1, which is stabilized by a pyrrole‐based bis(phosphinimine) pincer ligand (L=κ3‐NNN'=2,5‐[iPr2P=N(4‐iPrC6H4)]2‐N'(C4H2)−), serves as a versatile platform for the dehydrogenation of group 14 substrates. Reaction with primary and secondary silanes and germanes (MesSiH3, Et2SiH2, Ph2GeH2, tBuGeH3; Mes=mesityl) liberates H2 and yields base‐stabilized tetrylene compounds of the form κ2‐L(CO)Rh(ER2) (E=Si: R=Mes, H, 2; R=Et, 5; E=Ge: R=Ph, 6; R=tBu, H, 8). The ":ER2" fragment in these species bridges between the rhodium center and a phosphinimine donor. Preliminary reactions between pinacol (Pin) and κ2‐L(CO)Rh(ER2), E=Si, Ge, indicate that such complexes can serve as silylene and germylene synthons, releasing :ER2 and catalytically generating PinER2. In contrast, combination of complex 1 and MesGeH3 does not yield the anticipated dehydrogenation product, but rather, transmetalation similar to that observed upon reaction between 1 and 3,5‐dimethylphenylborane prevails. [ABSTRACT FROM AUTHOR]

This document is a scientific article discussing the synthesis and characterization of various chemical compounds. The authors provide detailed information about the experimental procedures, yields, and physical properties of the compounds. They also include data from spectroscopic techniques such as infrared (IR) spectra, nuclear magnetic resonance (NMR) spectra, and high-resolution mass spectrometry (HRMS) results. The information presented in this article can be valuable for researchers studying organic chemistry and conducting similar experiments. The authors acknowledge funding from the NSF MRI program and dedicate their work to the memory of Dr. Michael P. Jennings. Additional supporting information and a graph can be found online. [Extracted from the article]

The [1,2]‐Brook rearrangement stands as a potent technique for constructing complex molecules. In this study, we showcase its power in the dearomatization of aromatic N‐heterocycles. Through a concise four‐step process that integrates lithiation, nucleophilic addition, Brook rearrangement and dearomatization reaction, we demonstrate a versatile strategy for generating diverse non‐aromatic N‐heterocycles which exhibit ambident reactivities. Various acyl silanes, halo‐pyridines, and quinolines have been explored within this context. The synthetic utility of this methodology is demonstrated through the construction of complex architectures. [ABSTRACT FROM AUTHOR]

Nilutamide (1) of the NO2 group can be converted to NH2 by addition of triethyl silane and Wilkinson's catalyst to give amino compound (2) via reduction. It is further treated with t_BuONO by TMSN3 in RB flask containing CH3CN to give 3-(4-(4-azido-3-(trifluoromethyl) phenyl)-5-5-dimmethylimidazolidine-2,4-dione (3). Azide furthermore reacted with different terminal alkynes in the presence of Sharpless catalyst to form 5,5-dimethyl-3-(4-(4-phenyl-1H-1,2,3-triazol-1-yl)-3-trifluoromethyl imidazolidine-2,4-diones(4a-4j) with favorable yields depicted (scheme-I) in this manuscript. All the compounds were screened for in vitro anti-cancer activity, among them compound 4h containing the 4-CN group showed highest anticancer activity PC3=-1.94±1.16µM and DU-145=1.54±0.32 and MCF-7=1.43±0.92 µM. Compound 4d NO2 group resulting compound 4d exhibited PC3 3.38±2.07 and DU-145 =3.58±1.57 µM. Compound 4C containing Ome group PC3=2.10±1.38, DU-145=1.57±0.32 and MCF-7=2.08±1.64 µM as IC50 in µM, Etoposide is used as a reference. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: With the increasing demand for homoallylic silanes and allylic silanes, the highly efficient and regioselective hydrosilylations of conjugated dienes are urgently needed. Herein, we developed a Ni‐catalyzed regiodivergent hydrosilylation of aromatic conjugated dienes by adjusting the temperature and ligands. Under low temperature (–30 °C), an eternal‐ligand‐free system (Ni/t‐BuOK) can efficiently facilitate the 3,4‐anti‐Markovnikov hydrosilylation to provide homoallylic silanes via electrophilic activation process; under room temperature (25 °C), a ligand‐controlled system (Ni/t‐BuOK/PPh3) can eventuate the 3,4‐Markovnikov hydrosilylation to produce allylic silanes via Chalk‐Harrod process. Both systems are compatible with various conjugated dienes and primary silanes in excellent yields and regioselectivities. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: With the increasing demand for homoallylic silanes and allylic silanes, the highly efficient and regioselective hydrosilylations of conjugated dienes are urgently needed. Herein, we developed a Ni‐catalyzed regiodivergent hydrosilylation of aromatic conjugated dienes by adjusting the temperature and ligands. Under low temperature (–30 °C), an eternal‐ligand‐free system (Ni/t‐BuOK) can efficiently facilitate the 3,4‐anti‐Markovnikov hydrosilylation to provide homoallylic silanes via electrophilic activation process; under room temperature (25 °C), a ligand‐controlled system (Ni/t‐BuOK/PPh3) can eventuate the 3,4‐Markovnikov hydrosilylation to produce allylic silanes via Chalk‐Harrod process. Both systems are compatible with various conjugated dienes and primary silanes in excellent yields and regioselectivities. [ABSTRACT FROM AUTHOR]

Cementitious materials can be treated with organosilicon compounds (silanes) to achieve a water‐repellent effect. However, the influence of silanes on cement hydration is still not fully understood. For this reason, we studied the hydration of the main Portland cement phase (C3S ‐ tricalcium silicate) and the interaction with iBTES (isobutyltriethoxysilane), iOTES (isooctyltriethxysilane) and nOTES (n‐octyltriethoxysilane) by isothermal calorimetry and in‐situ X‐ray diffraction (XRD). The results show that C3S hydration is initially retarded and subsequently accelerated by iBTES and iOTES. In addition to the hydration process, the crystal growth of the portlandites (calcium hydroxide) is also affected by the silanes. The XRD results indicate that the portlandites grow significantly more plate‐like. In this context, the influence of the silanes on the portlandite crystallization was therefore also recorded in a special experimental setup. From the scanning electron microscope images it can be shown that all portlandite crystals grown in the presence of silanes have a platelike morphology. This is due to the fact that the hexagonal surfaces of the portlandite are covered by silanes and thus the growth direction of the crystals is affected. The modified portlandite crystals indicate that silanes also influence the microstructure of the cement paste and therefore its chemical and mechanical properties. [ABSTRACT FROM AUTHOR]

Group I alkoxides are highly active precatalysts in the heterodehydrocoupling of silanes and amines to afford aminosilane products. The broadly soluble and commercially available KOtAmyl was utilized as the benchmark precatalyst for this transformation. Challenging substrates such as anilines were found to readily couple primary, secondary, and tertiary silanes in high conversions (>90 %) after only 2 h at 40 °C. Traditionally challenging silanes such as Ph3SiH were also easily coupled to simple primary and secondary amines under mild conditions, with reactivity that rivals many rare earth and transition‐metal catalysts for this transformation. Preliminary evidence suggests the formation of hypercoordinated intermediates, but radicals were detected under catalytic conditions, indicating a mechanism that is rare for Si−N bond formation. [ABSTRACT FROM AUTHOR]

Improvement of thermal stability of silicone-based coatings was the main objective of this study. In this study bromoacetic acid (BAA) was reacted with 3-(mercaptopropyl) trimethoxy silane (MPTS) and trimethoxy silyl propyl thioacetic acid (TSTA) was produced. Also, bromoacetic acid (BAA) was reacted with 3-(triethoxysilyl) propylamine (APTS) and triethoxysilyl propylamino acetic acid (TSPA) was synthesized. Finally, from a reaction between trimellitic anhydride (TMA) and APTS, trimellitylimidopropyl triethoxysilane (TMIS) resulted. Compounds containing carboxylic acids and trimethyl silane were obtained in all of these reactions. Furthermore, hybrid coatings based on methacrylated bisphenol A epoxy (MBAE) and the synthesized carboxylic acids were obtained by photopolymerization. Polycarbonate substrates were utilized for preparation of the transparent hybrid films. Then the solvent resistance, hardness and gel content, as well as the adhesion of the coatings, were measured as physical and mechanical properties. According to the obtained results, these properties of the hybrid coatings were improved with the increase in alkoxysilanes and sol–gel precursor contents. The surface morphology was characterized by scanning electron microscopy (SEM). The results showed that silica particles were not dispersed homogenously at the molecular level in the hybrid system. Also, the thermogravimetric analysis results indicated that alkoxysilanes enhanced the thermal oxidative stability of the hybrid coatings. [ABSTRACT FROM AUTHOR]

The emerging field of Lewis acidic silanes demonstrates the versability of molecular silicon compounds for catalytic applications. Nevertheless, when compared to the multifunctional boron Lewis acid B(C6F5)3, silicon derivatives still lack in terms of reactivity. In this regard, we demonstrate the installation of perfluorotolyl groups (TolF) on neutral silicon atoms to obtain the respective tetra‐ and trisubstituted silanes Si(TolF)4 and HSi(TolF)3. These compounds were fully characterized including SC‐XRD analysis but unexpectedly showed no significant Lewis acidity. By using strongly electron‐withdrawing perfluorocresolato groups (OTolF) the tetrasubstituted silane Si(OTolF)4 was obtained, bearing an 8 % increased Δδ(31P) shift when applying the Gutmann‐Beckett method, compared to literature‐known Si(OPhF)4. Ultimately the heteroleptic Si(PhF)2pinF was successfully synthesized and fully characterized including SC‐XRD analysis, introducing a highly Lewis acidic silicon atom holding two silicon‐carbon bonds. [ABSTRACT FROM AUTHOR]

The growing ecological awareness of society and increasingly stringent legal requirements regarding environmental protection and the strategy of implementing the principles of sustainable development force the search for and continuous development of environmentally friendly solutions in the field of polymer materials technology. One of the directions is the use of raw materials from renewable sources. For this reason, the research object of the presented work was natural rubber composites containing a filler of plant origin in the form of ground horsetail (HT) biomass. Despite its health-promoting properties, it is commonly considered a weed. What's more, the ubiquitous occurrence and surplus make it a valuable source of waste biomass for management. Taking into account the limitations resulting from the hydrophilic nature of the lignocellulosic filler, and the related poor adhesion to the non-polar elastomer matrix, the horsetail filler was modified with organoalkoxysilanes. The study used silane compounds containing groups that can affect the properties of vulcanizates in various ways, such as vinyltriethoxysilane (VTES), 3,3′-Tetrathiobis(propyl-triethoxysilane) (TESPTS), 3-(aminopropyl)triethoxysilane (APTES), 3-(chloropropyl)triethoxysilane (CPTES) and octyltriethoxysilane (OTES). The biomass in the form of field horsetail was previously modified with selected silanes. Then, the bioadditive prepared in this way was applied to rubber mixtures. The process of modifying the natural filler contributed to structural changes in the lignocellulosic material, which may indicate the effective attachment of silane compounds to the horsetail surface. The results of the contact angle analysis show that the treatment strongly influenced the surface characteristics of the fillers, making them more hydrophobic. The results show that the type of silane coupling agent affects not only the processing associated with the vulcanization process but also the mechanical properties of the NR vulcanizates. This phenomenon is probably the result of increased rubber-bioadditive interaction and improved filler dispersion. Moreover, all composites with modified HT, show a greater flame permanence time than the one using unmodified filler. [ABSTRACT FROM AUTHOR]

This study investigated the effect of silane-based silica (SiO2) Janus nanoparticles (JNPs) on stabilizing the foam generated by different types of gases. Two types of SiO2 JNPs were synthesized through surface modification using HMDS and APTS silane compounds. Static analyses were conducted to examine the impact of different concentrations of the synthesized nanoparticles in various atmospheres (air, CO2, and CH4) on surface tension, foamability, and foam stability. The results indicated that the synthesized SiO2 JNPs and bare SiO2 nanoparticles exhibited nearly the same ability to reduce surface tension at ambient temperature and pressure. Both of these nanoparticles reduced the surface tension from 71 to 58–59 mN m−1 at 15,000 ppm and 25 °C. While bare SiO2 nanoparticles exhibited no foamability, the synthesis of SiO2 JNPs significantly enhanced their ability to generate and stabilize gas foam. The foamability of HMDS-SiO2 JNPs started at a higher concentration than APTS-SiO2 JNPs (6000 ppm compared to 4000 ppm, respectively). The type of gas atmosphere played a crucial role in the efficiency of the synthesized JNPs. In a CH4 medium, the foamability of synthesized JNPs was superior to that in air and CO2. At a concentration of 1500 ppm in a CH4 medium, HMDS-SiO2 and APTS-SiO2 JNPs could stabilize the generated foam for 36 and 12 min, respectively. Due to the very low dissolution of CO2 gas in water at ambient pressure, the potential of synthesized JNPs decreased in this medium. Finally, it was found that HMDS-SiO2 JNPs exhibited better foamability and foam stability in all gas mediums compared to APTS-SiO2 JNPs for use in oil reservoirs. Also, the optimal performance of these JNPs was observed at a concentration of 15,000 ppm in a methane gas medium. [ABSTRACT FROM AUTHOR]

Inhalation is a major route by which human exposure to substances can occur. Resources have therefore been dedicated to optimize human-relevant in vitro approaches that can accurately and efficiently predict the toxicity of inhaled chemicals for robust risk assessment and management. In this study—the IN vitro Systems to PredIct REspiratory toxicity Initiative—2 cell-based systems were used to predict the ability of chemicals to cause portal-of-entry effects on the human respiratory tract. A human bronchial epithelial cell line (BEAS-2B) and a reconstructed human tissue model (MucilAir, Epithelix) were exposed to triethoxysilane (TES) and trimethoxysilane (TMS) as vapor (mixed with N2 gas) at the air-liquid interface. Cell viability, cytotoxicity, and secretion of inflammatory markers were assessed in both cell systems and, for MucilAir tissues, morphology, barrier integrity, cilia beating frequency, and recovery after 7 days were also examined. The results show that both cell systems provide valuable information; the BEAS-2B cells were more sensitive in terms of cell viability and inflammatory markers, whereas MucilAir tissues allowed for the assessment of additional cellular effects and time points. As a proof of concept, the data were also used to calculate human equivalent concentrations. As expected, based on chemical properties and existing data, the silanes demonstrated toxicity in both systems with TMS being generally more toxic than TES. Overall, the results demonstrate that these in vitro test systems can provide valuable information relevant to predicting the likelihood of toxicity following inhalation exposure to chemicals in humans. [ABSTRACT FROM AUTHOR]

SiOx films, frequently derived from amino silane precursors, have found several applications with high added value. Although frequently used, the deposition of coatings from Tris(dimethyl amino) silane (TDMAS) has been reported to demand considerable amounts of energy, mainly due to the difficulty of oxidizing such compounds. As is well known, Plasma-enhanced atomic layer deposition (PEALD) is able to improve the oxidation efficiency, even under low processing temperatures. Owing to this, PEALD can be considered a very promising technique for the deposition of SiOx coatings. In this work, the deposition of silicon oxide films using TDMAS at 150 °C has been investigated. The effect of the plasma oxidation time (6 to 18 s) and atmosphere composition (pure O2 or O2 + Ar) on the chemical structure, elemental composition, and chemical bonding state of the films has also been evaluated. Increasing the plasma oxidation time in pure O2 resulted in a larger proportion of retained C (Si-CH3), whereas N was preserved in the structure (Si-N). On the other hand, the formation of SiOx films from TDMAS is favored in shorter oxidation times and O2 + Ar plasmas. [ABSTRACT FROM AUTHOR]

Phosphorus‐nitrogen (PN) adamantanoid cages are valuable precursors for materials chemistry, but their syntheses are based on harsh methods that sometimes require access to restricted reagents. We report a new and scalable synthesis of PN adamantanoid compounds by chlorosilane elimination between bis‐silylated amines and phosphorus trichloride. We further study the mechanism of the recently‐reported four‐fold oxidation of such cages with Me3SiN3 to yield tetravalent tetrahedral connectors for materials chemistry. Reaction monitoring and kinetic modelling revealed the key rate‐limiting step, but attempts to accelerate this using Lewis acid additives were unsuccessful. Nevertheless, a new four‐fold oxidized PN‐adamantanoid cage has been prepared and structurally characterized. [ABSTRACT FROM AUTHOR]

In this paper, a new type of borasilsesquioxanes was synthesized through a condensation process, and its reactivity in catalytic hydrosilylation reactions with silanes, siloxanes, and silsesquioxanes was investigated. The obtained compounds were mostly obtained in >90% yield. They were fully characterized using spectroscopic (1H, 13C, 29Si NMR) and spectrometric (MALDI-TOF-MS) methods. The next stage of the research involved studying the thermogravimetric properties of the borasilsesquioxanes. By analyzing the different stages of decomposition using spectroscopic techniques (NMR, ATR-FTIR, Raman) and microscopic imaging, it was found that the structure of the borasilsesquioxanes changed during the pyrolysis process and polymer compounds were formed. [ABSTRACT FROM AUTHOR]

Enhancing the flame retardancy with minimal impact on the mechanical and thermal performances of polymers remains a challenge. This study synthesized a phosphorus/nitrogen‐containing silane compound (D) using polyformaldehyde, KH‐550, and 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) as raw materials through the Kabachnik‐Fields reaction. After that, D was grafted onto the surface of graphene after hydrothermal treatment to obtain a nano hybrid flame retardant (D‐GR). And D‐GR/EP composites exhibited good flame resistance (LOI = 30.1% and UL‐94 reaches the V‐1 rating) even if the load on D‐GR was 1 wt%. Indeed, the total heat release, the peak heat release rate (PHRR), and the total smoke release of 1% D‐GR/EP dropped by 13.54%, 28.62%, and 44.32%, respectively, in comparison to pure EP. The mechanical performance of 1% D‐GR/EP was effectively maintained, as indicated by the results of impact, tensile and flexural tests. A systematic evaluation indicated that the accession of D‐GR effectively inhibited smoke and heat releases that are ascribed to the synergistic effect of phosphorus/nitrogen‐containing silane compound and graphene. In this study, a facile method was provided for the synthesis of halogen‐free flame‐retardant epoxy composites with superior performances. The combustion products of the as‐prepared composites complied with green and environmental protection standards. [ABSTRACT FROM AUTHOR]

In this article we report that a cationic version of Akiba's BiIII complex catalyzes the reduction of amides to amines using silane as hydride donor. The catalytic system features low catalyst loadings and mild conditions, en route to secondary and tertiary aryl‐ and alkylamines. The system tolerates functional groups such as alkene, ester, nitrile, furan and thiophene. Kinetic studies on the reaction mechanism result in the identification of a reaction network with an important product inhibition that is in agreement with the experimental reaction profiles. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries have emerged as the preferred choice for rechargeable power sources due to their ability to deliver high voltage, high energy density, and minimal selfdischarge, making them ideal for electronic devices and energy storage applications. Among the most commonly employed industrial lithium-ion batteries is the 18650 commercial battery, measuring 18x65 mm, renowned for its rechargeable capabilities. Nonetheless, their widespread use faces significant safety challenges when subjected to extreme thermal or electrical stress. This study aims to enhance the safety and electrochemical performance of 18650-type battery cells at room temperature while mitigating the flammability risks associated with their carbonate-based electrolytes by incorporating an eco-friendly additive, vinyl triethoxysilane (VTES). Introducing 5 vol.% VTES into the electrolyte proved to be the optimal composition, resulting in improved cycling performance. This improvement can be attributed to the formation of stable and uniform surface films on both cathode and anode surfaces. These findings underscore the promise of VTES as an additive to enhance the safety and electrochemical performance of lithium-ion batteries, even at an industrial scale. To quantitatively and qualitatively assess the impact and performance of the VTES organic silicon compound, a comprehensive set of thermal and electrochemical analyses, including EDX, SEM, LSV, CV, EIS, TGA/DSC, and SET, were conducted. [ABSTRACT FROM AUTHOR]

Novel P,O‐type ligands, N‐disulfonyl bicyclic bridgehead phosphorus triamides, were synthesized and utilized in Pd‐catalyzed hydrosilylation involving tertiary silanes, unactivated alkenes, and conjugated dienes. The ligand displayed a remarkable level of reactivity for alkene hydrosilylation with tertiary silanes and its use resulted in a significant improvement in the regioselectivity of diene hydrosilylation towards 1,2‐hydrosilylation. X‐ray crystallographic analysis confirmed the bidentate nature of the ligand, with coordination of phosphorus and oxygen. Control experiments provided evidence for the formation of Pd0 species and the reversibility of Pd−H insertion in the reaction mechanism. Density functional theory (DFT) computations supported the importance of the hemilabile P,O ligand in stabilizing both the rate‐determining transition state of Pd−H insertion and the transition state of reductive elimination that determines the regioselectivity. [ABSTRACT FROM AUTHOR]

The disposal of tires at the end of their lifespan results in societal and environmental issues. To tackle this, recycling and reuse are effective solutions. Among various recycling methods, devulcanization is considered to be a very sustainable option, as it involves the controlled breakdown of crosslinks while maintaining the polymer backbones. The objective of this study is to develop a sustainable devulcanization process for passenger car tire rubber using silanes. In this study, a thermo-mechanical–chemical devulcanization process was conducted to screen six potential devulcanization aids (DAs). Silanes were chosen as they are widely used in tire rubber as coupling agents for silica. The efficiency of the devulcanization was studied by the degree of network breakdown, miscibility of the devulcanized material, and mechanical properties of the de- and revulcanized material. Compared to the parent compound, a 55–60% network breakdown was achieved for the devulcanizate along with 50–55% of tensile strength recovery. In addition to superior devulcanization efficiency, this DA offers a sustainable alternative to the conventional ones, such as di-phenyl-di-sulphide, due to its compliance with safety regulations. The devulcanizate can be utilized in high-performance applications, such as tires and seals, while 100% devulcanizate can be employed in low-strength technical rubber products. [ABSTRACT FROM AUTHOR]

Purpose: This study evaluated the effect of an aromatic silane compound and acidic functional monomer on the bond strength of fused quartz. Materials and Methods: A total of 264 disk specimens were fabricated from fused quartz for shear bond testing. Two silane compounds were used: 3-(trimethoxysilyl)propyl methacrylate (3-TMSPMA) and 3-(4-methacryloyloxyphenyl)propyltrimethoxysilane (3-MPPTS). As acidic functional monomers, 4-methacryloyloxyethyl trimellitate (4-MET) and 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) were used. The disks were primed with one of each silane compound with or without the acidic functional monomer of the same molarity. The specimens were bonded with a tri-n-butylborane (TBB) initiated luting material. The shear bond strength was determined before and after 10,000 thermocycles. Bond strength was statistically evaluated with Kruskal-Wallis, Mann-Whitney U-, and Steel-Dwass tests. To test dye penetration, the specimens were immersed in 0.5 wt% fuchsin solution for 24 h after priming with each condition, bonding, and 10,000 thermocycles. The dye penetration area was determined by observing the backside of the bonded specimen with an optical microscope. The relationship between the shear bond strength and dye penetration ratio was analyzed with Spearman's rank correlation test. Results: The highest post-thermocycling bond strengths in the 1 mol% and 2 mol% groups were 3-TMSPMA + 10-MDP and 3-MPPTS + 10-MDP. Spearman's rank correlation coefficient between shear bond strength and dye penetration area was γ = -0.7519, indicating a strong negative correlation. Conclusion: The surface treatments of 3-TMSPMA and 3-MPPTS combined with 10-MDP yielded higher bond strength after 10,000 thermocycles than those combined with 4-MET, despite the similarity in molarity. The shear bond strength was negatively correlated with the dye penetration area. [ABSTRACT FROM AUTHOR]

Composite materials show improved properties compared to pristine materials, in particular when the filler is dispersed homogeneously in the matrix. For polymer–clay composites, different strategies exist to improve clay mineral dispersion in the polymer matrix. In this study, an innovative approach is suggested which consists of forming a talc-like structure directly in a polymer matrix using a silanized polymer as the silicon source. Poly(ethylene glycol) methyl ether of different average molar masses (Mn = 350, 500, 750, 1900 g mol−1) were functionalized with (3-isocyanatopropyl)triethoxysilane and added to the ethanolic solutions of magnesium nitrate. 1H–29Si CPMAS solid state NMR experiments revealed partial condensation of silane compounds, and FTIR analysis confirmed the presence of both Si–O and Mg–O bonds, but an additional proof of the Si–O–Mg bond is needed to prove the formation of such a structure. [ABSTRACT FROM AUTHOR]

Herein we report a mild synthesis of propargyl silanes from terminal alkynes. We exploit a bromonaphthyl-substituted silane as a silylmethyl electrophile surrogate, which participates in a Sonogashira reaction after an aryl-to-alkyl Pd-migration. Twenty-seven propargyl silanes were obtained in up to 88% yield. The obtained products were versatile building blocks that can be used in addition to electrophiles, triple bond hydrogenation or silyl group cleavage with acid or fluoride sources. [ABSTRACT FROM AUTHOR]

Silanes are important compounds in industrial and synthetic chemistry. Here, we develop a general approach for the synthesis of disilanes as well as linear and cyclic oligosilanes via the reductive activation of readily available chlorosilanes. The efficient and selective generation of silyl anion intermediates, which are arduous to achieve by other means, allows for the synthesis of various novel oligosilanes by heterocoupling. In particular, this work presents a modular synthesis for a variety of functionalized cyclosilanes, which may give rise to materials with distinct properties from linear silanes but remain challenging synthetic targets. In comparison to the traditional Wurtz coupling, our method features milder conditions and improved chemoselectivity, broadening the functional groups that are compatible in oligosilane preparation. Computational studies support a mechanism whereby differential activation of sterically and electronically distinct chlorosilanes are achieved in an electrochemically driven radical‐polar crossover mechanism. [ABSTRACT FROM AUTHOR]

Palladium‐catalyzed carbonylation reactions aid as potent tools for the insertion of carbonyl unit(s) in a wide array of molecules possessing vast number of applications in multiple domains. An efficient and facile protocol has been reported for the carbonylative Suzuki (CO−S) and carbonylative Hiyama (CO−H) coupling of aryl triazenes using phenyl boronic acid and triethoxy(phenyl)silane respectively via a Pd‐catalysis in combination with Ionic liquids (ILs). Four different ILs have been employed as solvent/reagent/promotor(s) to afford the targeted products in reasonably good yields. As per the predictive mechanism, an in situ generated N‐Heterocarbene‐Ionicliquid‐Palladium (NHC‐IL‐Pd) species serve as a regenerative catalyst while the N‐formyl saccharin (NFSac), a non‐hazardous and commercially available crystalline compound was used as carbon monoxide (CO) surrogate playing important roles to accomplish the desired products in good yields. [ABSTRACT FROM AUTHOR]

Over the years, ground and surface water has been reported to be contaminated with phosphates. These phosphates are known to cause various diseases and if present in excess can lead to eutrophication. The known silane chemistry has not been thoroughly investigated for the sensing of anions. In the current study four new triazole based silanes have been prepared by the renowned Click Chemistry for the selective and sensitive detection of dihydrogen phosphate. The synthesized compounds were well characterized by various spectroscopic techniques and their absorptive and emissive responses were investigated for the recognition of dihydrogen phosphate ions. The binding ratio between triazole based silane chemosensor and dihydrogen phosphate has been discovered from Job's plot and was also confirmed by non‐linear fitting method. The value of association constant was found to be 571.18 M−1. The limit of detection (LOD) and limit of quantitation (LOQ) were calculated by fluorescence spectroscopy. The results obtained clearly illustrated that triazole based silane could be used as a potent chemosensor for selective and sensitive recognition of dihydrogen phosphate. Further, the possible binding site of chemosensor for dihydrogen phosphate has been identified from 1H NMR studies and DFT calculations. At last real sample analysis was performed to check the practical applicability of chemosensor. [ABSTRACT FROM AUTHOR]

Since the last decade, hyperbranched polymers (HBPs) have gained wider theoretical interest and practical applications in sensor technology due to their ease of synthesis, highly branched structure but dimensions within nanoscale, a larger number of modified terminal groups and lowering of viscosity in polymer blends even at higher HBP concentrations. Many researchers have reported the synthesis of HBPs using different organic-based core-shell moieties. Interestingly, silanes, as organic-inorganic hybrid modifiers of HBP, are of great interest as they resulted in a tremendous improvement in HBP properties like increasing thermal, mechanical and electrical properties compared to that of organic-only moieties. This review focuses on the research progress in organofunctional silanes, silane-based HBPs and their applications since the last decade. The effect of silane type, its bi-functional nature, its influence on the final HBP structure and the resultant properties are covered in detail. Methods to enhance the HBP properties and challenges that need to be overcome in the near future are also discussed. [ABSTRACT FROM AUTHOR]

Herein we report an efficient hydrosilylation strategy to selectively defunctionalize biomass‐derived levulinic acid into value‐added chemicals such as pentane‐1,4‐diol, pentan‐2‐ol, 2‐MTHF and C5 hydrocarbons by using cost‐effective silanes and the commercially available catalyst B(C6F5)3 at room temperature. All reactions work well in chlorinated solvents but, as a greener alternative, most reactions can be run in toluene or solvent‐less. [ABSTRACT FROM AUTHOR]

A convenient and selective hydrosilylative transformation of chemically inert primary amides (26 examples) into the corresponding primary amines with key functional group tolerance has been developed by using simple well-defined O,N,N,O donor salen-based earth abundant manganese(III) complexes under mild conditions. On a slight modification of the reaction condition by adding the blocking agent secondary amide, the transformation of primary amides to amines stops in the intermediate nitrile state (9 examples). The same catalyst also has the capability to reduce nitriles to amines (15 examples) using inexpensive silanes such as polymethylhydrosiloxane (PMHS). Mechanistic studies and DFT calculations are also carried out to understand the reaction mechanism and chemoselectivity. In this catalytic transformation, the manganese catalyst activates the primary amides and the overall reduction proceeds via the dehydration of the primary amides into the corresponding nitriles, which are then reduced into the corresponding primary amines. [ABSTRACT FROM AUTHOR]

Polypyrrole adhesion to indium–tin oxide electrodes was improved by adding pre-hydrolyzed alkoxysilanes to the electrodeposition media. The pyrrole oxidation and film growth rates were studied by potentiostatic polymerization in acidic media. The morphology and thickness of the films were studied by contact profilometry and surface-scanning electron microscopy. The bulk and surface semiquantitative chemical composition was studied by Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. Finally, the adhesion was studied by scotch-tape adhesion test, where both alkoxysilanes showed a significant improvement in adhesion. We proposed a hypothesis for the improvement in adhesion, that involves the formation of siloxane material as well as in situ surface modification of the transparent metal oxide electrode. [ABSTRACT FROM AUTHOR]