Silane sulfur-containing silanes

ZnO influences the characteristics of a compound twofold Primarily, ZnO influences the kinetics of the silica-silane reaction. Secondly, ZnO enhances the scorching behavior of a sulfur-containing coupling agent. This effect is clearly visible when looking at the G at 100% strain and the 300% modulus. 

The exquisite synthetic potential of thiophene-based dienoxy silane 90 (Scheme 44) as a nucleophilic homologative reactant vis-a-vis protected hydroxy aldehydes, such as 11, was recently exploited by Rassu and coworkers to enter the scantly investigated domain of sulfur-containing... 

Trimethyl(trifluoromethyl)silanc reacts with the derivatives of four- and six valent sulfur-containing mobile halogen atoms to form the trifluoroniethyl deri vatives. Trifluoromethylation with trimethyl(trifluoromethyl)silane has also been used in the preparation of a trifluoro-methylatcd sugar derivative. 

The reaction of a bifunctional organosilane with precipitated silica involves the hydrophobation of the alkoxy group of the silane with a surface silanol group of the silica, followed by reaction of the sulfur-containing function of the silane with an olefin group of the elastomer to afford a covalently bonded structure. This silane-coupled silica is useful in improving the abrasion resistance of silicas to levels of carbon blacks, and promoted their use in the treads of radial passenger tires. 

Solid palladium scavengers, PVPy, QTU were pmchased from commercial somces. The mesoporous silica material, S102-SH, was prepared via reaction of SBA-15 (110 A pore diameter) with 3-mercaptopropyltrimethoxysilane (16). Specifically, a toluene suspension of SBA-15 and 3-mercaptopropyltrimethoxysilane was heated at reflux for two days under Ar. Water was then added to promote the cross-linking and the mixture was heated at reflux for an additional day. The sohds were filtered and washed with copious amounts of toluene, hexanes, and methanol to remove unreacted silanes. The solids were finally Soxhlet extracted with dichloromethane at reflux temperature for 3 days, dried, and stored in a nitrogen dry box. The final solid contained 7.5 wt% sulfur (2.3 mmole S/g solid). 

The crude product containing some silicide evolves, in contact with hydrochloric or sulfuric acids, a mixture of borane and silane which may ignite. 

In 1992, Crabtree and co-workers reported the first nickel catalyst effective for silane alcoholysis.161 The complex, [Ni(tss)]2 (tss = salicylaldehyde thiosemicarbazone), bears a ligand that contains O and N donor groups and a semicarbazide sulfur. Alcoholysis of Et3SiH with ethanol or methanol occurs at room temperature in 50% dimethyl sulfoxide-benzene. However, the reaction is inhibited in the presence of strong donor ligands, H2, or atmospheric pressure of CO. 

Other silanes, containing amino, sulfur, halogen or phenyl groups are also applied with various rubber types, as summarized in table 8.7.55... 

Similarly, l-(phenoxyalkyl)benzotriazoles 456 can be lithiated to give the corresponding acyllithiums 457, which have been used for the preparation of alkanoyl silanes and functionalized ketones (Scheme 120)665. Hydrolysis of adducts 458 was performed in refluxing aqueous ethanol (50%) containing 5% of sulfuric acid for 10 min. For acyl silanes, milder reaction conditions were used. When 1,4-dibromobutane was used as dielectrophile, alkyl, aryl, alkenyl and alkynyl 1,4-diketones were prepared in 74-86% yield666. 

Stabilization of a lipid membrane onto a solid support by covalent attachment also provides the physical stability necessary for the development of practical sensors. An oriented membrane can be prepared by allowing self-assembly of individual amphiphilic molecules onto a solid surface through either the reaction of terminal silane moieties with a hydroxylated surface to form a silyl ether [33,34], or by the reaction of sulfur-terminated compounds (alkylthiols or disulfides) with gold surfaces [35,36]. A variety of species, both with and without polar head groups, have been deposited onto surfaces such as glass, quartz, silicon, and gold [37-39]. These include phospholipids, fatty acids, and fatty amines which were synthetically altered so as to contain either a silyl chloride or a thiol moiety at the terminus of the acyl chain [40]. Both monolayers... 

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