Silanes

<p>Alkenylsilane Cross-Coupling Agent<br>The cross-coupling reaction is a highly useful methodology for the formation of carbon-carbon bonds. It involves two reagents, with one typically being a suitable organometallic reagent - the nucleophile - and the other a suitable organic substrate, normally an unsaturated halide, tosylate or similar - the electrophile.<br>1,3,5-Trivinyl-1,3,5-trimethylcyclotrisiloxane; D’3; Trimethyltrivinylcyclotrisiloxane; Trivinyltrimethylcyclotrisiloxane; 2,4,6-Trimethyl-2,4,6-trivinylcyclotrisiloxane<br>Reagent formation of styrenes and dienes.Undergoes “living” anion ring-opening polymerizationReagent for vinylations via cross-coupling protocolsExtensive review of silicon based cross-coupling agents: Denmark, S. E. et al. "Organic Reactions, Volume 75" Denmark, S. E. ed., John Wiley and Sons, 233, 2011<br></p>

<p>3-Aminopropyldiisopropylethoxysilane, 3-(diisopropylethoxysilyl)propylamine<br>Monoamino functional monoalkoxy silaneForms hydrolytically stable amino-functional bonded phases and monolayersPrimary amine coupling agent for UV cure and epoxy systemsUsed in microparticle surface modification<br></p>

<p>Alkyl Silane - Conventional Surface Bonding<br>Aliphatic, fluorinated aliphatic or substituted aromatic hydrocarbon substituents are the hydrophobic entities which enable silanes to induce surface hydrophobicity. The organic substitution of the silane must be non-polar. The hydrophobic effect of the organic substitution can be related to the free energy of transfer of hydrocarbon molecules from an aqueous phase to a homogeneous hydrocarbon phase. A successful hydrophobic coating must eliminate or mitigate hydrogen bonding and shield polar surfaces from interaction with water by creating a non-polar interphase. Although silane and silicone derived coatings are in general the most hydrophobic, they maintain a high degree of permeability to water vapor. This allows coatings to breathe and reduce deterioration at the coating interface associated with entrapped water. Since ions are not transported through non-polar silane and silicone coatings, they offer protection to composite structures ranging from pigmented coatings to rebar reinforced concrete. A selection guide for hydrophobic silanes can be found on pages 22-31 of the Hydrophobicity, Hydrophilicity and Silane Surface Modification brochure.<br>Acetoxytrimethylsilane; O-Trimethylsilyl acetate<br>Vapor pressure, 30 °: 35 mm<br></p>

<p>Olefin Functional Trialkoxy Silane<br>Silane coupling agents have the ability to form a durable bond between organic and inorganic materials to generate desired heterogeneous environments or to incorporate the bulk properties of different phases into a uniform composite structure. The general formula has two classes of functionality. The hydrolyzable group forms stable condensation products with siliceous surfaces and other oxides such as those of aluminum, zirconium, tin, titanium, and nickel. The organofunctional group alters the wetting or adhesion characteristics of the substrate, utilizes the substrate to catalyze chemical transformations at the heterogeneous interface, orders the interfacial region, or modifies its partition characteristics, and significantly effects the covalent bond between organic and inorganic materials.<br>Alkenylsilane Cross-Coupling Agent<br>The cross-coupling reaction is a highly useful methodology for the formation of carbon-carbon bonds. It involves two reagents, with one typically being a suitable organometallic reagent - the nucleophile - and the other a suitable organic substrate, normally an unsaturated halide, tosylate or similar - the electrophile.<br>Vinyltrimethoxysilane; Ethenyltrimethoxysilane; Trimethoxyvinylsilane; Trimethoxysilylethylene, VTMS<br>Viscosity: 0.6 cStCopolymerization parameters- e,Q: -0.38, 0.031Specific wetting surface area: 528 m2/gVapor pressure, 20 °C: 9 mmEmployed in two-stage and one-stage graft polymerization/crosslinking for polyethylene (PE)Copolymerizes with ethylene to form moisture crosslinkable polymersConverts arylselenyl bromides to arylvinylselenidesReacts with anhydrides to transfer both vinyl and methoxy and thus form the mixed diesterCross-couples with α-bromo esters to give α-vinyl esters in high eeUsed in microparticle surface modificationFor vinylationsAlkenyltrialkoxysilanes react w/ aryl bromides and iodides to form styrenes under fluoride- and ligand-free and aqeous conditionsReacts in presence of fluorideExtensive review of silicon based cross-coupling agents: Denmark, S. E. et al. "Organic Reactions, Volume 75" Denmark, S. E. ed., John Wiley and Sons, 233, 2011<br></p>

<p>Bridging Silicon-Based Blocking Agent<br>Used as a protecting group for reactive hydrogens in alcohols, amines, thiols, and carboxylic acids. Organosilanes are hydrogen-like, can be introduced in high yield, and can be removed under selective conditions. They are stable over a wide range of reaction conditions and can be removed in the presence of other functional groups, including other protecting groups. The tolerance of silylated alcohols to chemical transformations summary is presented in Table 1 of the Silicon-Based Blocking Agents brochure.<br>Di-tert-butylsilylbis(trifluoromethanesulfonate); Di-t-butylsilylbis(triflate); DTBS<br>More reactive than SID3205.0Converts 1,3-diols to cyclic protected 1,3-diolsReacts with 1,3-diols in preference to 1,2-diolsSummary of selective deprotection conditions is provided in Table 7 through Table 20 of the Silicon-Based Blocking Agents brochure<br></p>

<p>Siloxane-Based Silane Reducing Agent<br>Organosilanes are hydrocarbon-like and possess the ability to serve as both ionic and free-radical reducing agents. These reagents and their reaction by-products are safer and more easily handled and disposed than many other reducing agents. The metallic nature of silicon and its low electronegativity relative to hydrogen lead to polarization of the Si-H bond yielding a hydridic hydrogen and a milder reducing agent compared to aluminum-, boron-, and other metal-based hydrides. A summary of some key silane reductions are presented in Table 1 of the Silicon-Based Reducing Agents brochure.<br>Tetrakis(dimethylsiloxy)silane; M'4Q; 3,3-Bis(dimethylsiloxy)-1,1,5,5-tetramethyltrisiloxane<br>Viscosity: 1.1 cStCrosslinker for vinyl functional siliconesHigh molecular weight silane reducing agentExtensive review of silicon based reducing agents: Larson, G.; Fry, J. L. "Ionic and Organometallic-Catalyzed Organosilane Reductions", Wipf, P., Ed.; Wiley, 2007<br></p>

<p>Alkyl Silane - Conventional Surface Bonding<br>Aliphatic, fluorinated aliphatic or substituted aromatic hydrocarbon substituents are the hydrophobic entities which enable silanes to induce surface hydrophobicity. The organic substitution of the silane must be non-polar. The hydrophobic effect of the organic substitution can be related to the free energy of transfer of hydrocarbon molecules from an aqueous phase to a homogeneous hydrocarbon phase. A successful hydrophobic coating must eliminate or mitigate hydrogen bonding and shield polar surfaces from interaction with water by creating a non-polar interphase. Although silane and silicone derived coatings are in general the most hydrophobic, they maintain a high degree of permeability to water vapor. This allows coatings to breathe and reduce deterioration at the coating interface associated with entrapped water. Since ions are not transported through non-polar silane and silicone coatings, they offer protection to composite structures ranging from pigmented coatings to rebar reinforced concrete. A selection guide for hydrophobic silanes can be found on pages 22-31 of the Hydrophobicity, Hydrophilicity and Silane Surface Modification brochure.<br>n-Butyltrichlorosilane; Trichlorosilylbutane<br>Vapor pressure, 31 °C: 10 mm<br></p>

<p>Specialty Silicon-Based Blocking Agent<br>Used as a protecting group for reactive hydrogens in alcohols, amines, thiols, and carboxylic acids. Organosilanes are hydrogen-like, can be introduced in high yield, and can be removed under selective conditions. They are stable over a wide range of reaction conditions and can be removed in the presence of other functional groups, including other protecting groups. The tolerance of silylated alcohols to chemical transformations summary is presented in Table 1 of the Silicon-Based Blocking Agents brochure.<br>Chloromethyldimethylchlorosilane; (Chlorodimethylsilyl)chloromethane; Chloro(chloromethyl)dimethylsilane; CMDMCS<br>Can form cyclic products with appropriate 1,2-difunctional substratesUsed in analytical applications for greater ECD detectabilitySummary of selective deprotection conditions is provided in Table 7 through Table 20 of the Silicon-Based Blocking Agents brochure<br></p>

<p>(3-Trimethoxysilylpropyl)diethylenetriamine; N-[N'-(2-aminoethyl)aminoethyl]-3-aminopropytrimethoxysilane<br>Triamino functional trialkoxy silaneHardener, coupling agent for epoxiesγc of treated surfaces: 37.5 mN/mPrimary amine and two internal secondary amine coupling agent<br></p>

<p>Anhydride Functional Trialkoxy Silane<br>Silane coupling agents have the ability to form a durable bond between organic and inorganic materials to generate desired heterogeneous environments or to incorporate the bulk properties of different phases into a uniform composite structure. The general formula has two classes of functionality. The hydrolyzable group forms stable condensation products with siliceous surfaces and other oxides such as those of aluminum, zirconium, tin, titanium, and nickel. The organofunctional group alters the wetting or adhesion characteristics of the substrate, utilizes the substrate to catalyze chemical transformations at the heterogeneous interface, orders the interfacial region, or modifies its partition characteristics, and significantly effects the covalent bond between organic and inorganic materials.<br>3-Triethoxysilylpropylsuccinic anhydride<br>Viscosity: 20 cStCoupling agent for dibasic surfacesAcetic acid-catalyzed hydrolysis yields succinct acid derivativesHardener, coupling agent for for epoxy resins<br></p>

<p>Olefin Functional Trialkoxy Silane<br>Silane coupling agents have the ability to form a durable bond between organic and inorganic materials to generate desired heterogeneous environments or to incorporate the bulk properties of different phases into a uniform composite structure. The general formula has two classes of functionality. The hydrolyzable group forms stable condensation products with siliceous surfaces and other oxides such as those of aluminum, zirconium, tin, titanium, and nickel. The organofunctional group alters the wetting or adhesion characteristics of the substrate, utilizes the substrate to catalyze chemical transformations at the heterogeneous interface, orders the interfacial region, or modifies its partition characteristics, and significantly effects the covalent bond between organic and inorganic materials.<br>Alkenylsilane Cross-Coupling Agent<br>The cross-coupling reaction is a highly useful methodology for the formation of carbon-carbon bonds. It involves two reagents, with one typically being a suitable organometallic reagent - the nucleophile - and the other a suitable organic substrate, normally an unsaturated halide, tosylate or similar - the electrophile.<br>Vinyltriethoxysilane; Triethoxyvinylsilane; TEVS; VTES; Ethenyltriethoxysilane; Triethoxysilylethylene; Triethoxy(vinyl)silane<br>ΔHvap: 6.8 kcal/molΔHform: -463.5 kcal/molDipole moment: 1.69 debyeSpecific wetting surface area: 412 m2/gCopolymerization parameters- e,Q: -0.42, 0.028γc of treated surfaces: 25 mN/mVapor pressure, 20 °C: 5 mmSpecific heat: 0.25 cal/g/°Relative hydrolysis rate versus SIV9220.0, vinyltrimethoxysilane; 0.05Forms copolymers with ethylene for moisture induced coupling of polyethyleneCouples fillers or fiberglass to resinsSee VEE-005 for polymeric versionReacts with enamines to give (E)-β:-silylenamines, which cross-couple with aryl iodides to give β-aryl enaminesEmployed as a coupling agent, adhesion promoter, and crosslinking agentUsed in microparticle surface modification for fillersCompatible with sulfur and peroxide cured rubber, polyester, polyolefin, styrene, and acrylic based materialsFor vinylationsAvailable as an oligomeric hydrolysate, SIV9112.2Extensive review of silicon based cross-coupling agents: Denmark, S. E. et al. "Organic Reactions, Volume 75" Denmark, S. E. ed., John Wiley and Sons, 233, 2011<br></p>

<p>N,N-Bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane; N-triethoxysilylpropyl-N,N-bis(2-hydroxyethyl)amine; 2,2'-[[3- (triethoxysilyl)propyl]imino]bisethanol<br>Tertiary amino functional trialkoxy silaneTerminal dihydroxy-functionalityUrethane polymer coupling agentContains 2-3% hydroxyethylaminopropyltriethoxysilaneSpecific wetting surface: 252 m2/gEmployed in surface modification for preparation of oligonucleotide arrays 62% in ethanol<br></p>