3,3- dimethyl-silane

The first type of polycarbosilane synthesized by using ADMET methodology was a poly[carbo(dimethyl)silane].14c Linear poly(carbosilanes) are an important class of silicon-containing polymers due to their thermal, electronic, and optical properties.41 They are also ceramic precursors to silicon carbide after pyrolysis. ADMET opens up a new route to synthesize poly(carbosilanes), one that avoids many of the limitations found in earlier synthetic methods.41... 

Figure 8.14 Classes of poly[carbo(dimethyl)silanes] produced by ADMET.

TABLE 8.2 Characterization Data for Poly[carbo(dimethyl)silane]s... 

See also PBT degradation structure and properties of, 44-46 synthesis of, 106, 191 Polycaprolactam (PCA), 530, 541 Poly(e-caprolactone) (CAPA, PCL), 28, 42, 86. See also PCL degradation OH-terminated, 98-99 Polycaprolactones, 213 Poly(carbo[dimethyl]silane)s, 450, 451 Polycarbonate glycols, 207 Polycarbonate-polysulfone block copolymer, 360 Polycarbonates, 213 chemical structure of, 5 Polycarbosilanes, 450-456 Poly(chlorocarbosilanes), 454 Polycondensations, 57, 100 Poly(l,4-cyclohexylenedimethylene terephthalate) (PCT), 25 Polydimethyl siloxanes, 4 Poly(dioxanone) (PDO), 27 Poly (4,4 -dipheny lpheny lpho sphine oxide) (PAPO), 347 Polydispersity, 57 Polydispersity index, 444 Poly(D-lactic acid) (PDLA), 41 Poly(DL-lactic acid) (PDLLA), 42 Polyester amides, 18 Polyester-based networks, 58-60 Polyester carbonates, 18 Polyester-ether block copolymers, 20 Polyester-ethers, 26... 

Preparation of [l-(diethoxyphosphinyl)ethoxy]dimethyl-silane — Reaction of an aldehyde with a trialkyl phosphite in the presence of a silyl halide... 

Dinh is illustrative of the methods and their potential (Figure 4).1261 Hydrosilylation of enones like cydo-hexenone was conducted in two different ways. Under biphasic reaction conditions, an organic solvent like toluene containing the enone and phenyl-dimethyl silane was heated with a fluorocarbon solvent (perfluoromethylcyclohexane) containing a fluorous rhodium catalyst. The hydrosilylation reaction occurred over 10 h, and the reaction mixture was cooled and the phases were separated. Distillation of the residue from the organic phase gave the hydrosilylated products in excellent isolated yields... 

Preparation of model compounds and polyurethanes. A procedure for the preparation of the non-silicon containing monocarbamate and biscarbamate models has been reported previously (8). In order to obtain the silicon containing model compound, 5.0 g of bis(4-aminophenyl) dimethyl silane [synthesized according to Pratt, et.al (9)] was added to 7.0 g ethyl chloroformate at room temperature. A salt immediately formed. The mixture was refluxed for 15 min. The solution was then cooled, vacuum filtered, and recrystallized from ethanol to yield 1.0 g of a white powder MP 162-3 °C Anal. c20H26°4N2Si Calc. C, 62.17 H, 6.70 N, 7.23 Found C, 62.01 H, 6.79 N, 7.42. 

DIMETHYL SULFOXIDE ETHYLENE GLYCOL DIMETHYL SULFATE DIMETHYL SULFIDE ETHYL MERCAPTAN DIMETHYL DISULFIDE DIMETHYLAMINE ETHYLAMINE MONOETHANOLAMINE ETHYLENEDIAMINE DIMETHYL SILANE CYANOGEN... 

Ring nitrogens in pyrazines and the benzo derivatives react with electrophiles to form quaternary ammonium species such as iV-alkylpyrazinium salts and pyrazine iV-oxides. N-Alkylation has generally been performed by treatment with a reactive alkyl iodide. The N-1 nitrogen in 2(l//)-pyrazinone 5 is methylated using chloro(chloromethyl)dimethyl-silane followed by desilylation with cesium fluoride to yield l-methyl-2(l//)-pyrazinone <2000TL4933>. 

The reaction of an w-alkyl(chloro)(dimethyl)silane or w-trialkylchlorosilane of the type RMe2SiX or R3SiX (X = Cl) with a hydrothermally activated silica represents the second and more popular approach. Excellent mass transfer characteristics with peptides can be... 

The enantiomerically pure l-[(benzyl(dimethyl)silyl)methyl]pyrrolidine, obtained from ben-zyl(chloro)(dimethyl)silane and (5,)-2-(methoxymethyl)pyrrolidine , afforded after deprotonation and subsequent alkylation the diastereomerically pure (by NMR spectroscopy) (a-alkylben-zyl)silanes2. To obtain this high degree of diastereoselectivity, the alkylation had to be performed in the weakly complexing solvent diethyl ether. In THF a diastereomeric ratio of only 3 1 was found with iodomethane as alkylating agent. 

Zur selektiven N-Monoalkylierung von primaren Aminen kann man das Amin zunachst mit tert.-Butyl-chlor-dimethyl-silan N-silylieren, das isolierte N-Silyl-Derivat mit Butyl-lithium N-metallieren, anschlieBend mit einem Alkyl-halogenid umsetzen und schlieBlich die Silyl-Gruppe durch Behandlung mit trockenem Chlorwasserstoff abspalten1. 

Twenty-five years later, Burhard reported the preparation of permethylated. polysilane (2). These materials were, however, highly crystalline, insoluble white solids which evoked little scientific interest until recently when it was discovered that silane polymers could be used as thermal precursors to / -silicon carbide fibers (3-5). In this regard, Yajima and co-workers reported that poly (dimethyl) silane could be converted by the two-step process shown below to / -silicon carbide, a structural material of considerable industrial importance. 

Poly(styrene-f)-ferrocenyl dimethyl-silane) Sphere Silica nanopillars [90,160]... 

Hammaecher, C. and Portella, C. (2008) New 6-oxa-2-silabicyclo[2.2.0]hexanes by photochemical conversion of acyl(allyl) (dimethyl)silanes. Chemical Communications, 5833—5835. 

Silyl radicals have also been observed during /-irradiation of solid polysilanes. Tagawa and coworkers examined the EPR spectrum observed upon irradiation of solid poly-(dimethylsilane) and concluded that the spectrum corresponded to silyl radicals generated by homolysis of the silicon skeleton in the polysilane (equation 5)18. Indeed, the EPR spectrum of the poly(dimethylsilane) radical (13), with hyperfine splitting constants H) and a(y-1 H) of 0.813 and 0.046 mT respectively, corresponded remarkably well to that published for the dimethyl(trimethylsilyl)silyl radical [a( -1H) = 0.821 mT a(/-1H) = 0.047 mT]1. Radical (13) appears to be very stable in solid poly(dimethyl-silane), since the EPR signal was strong and clearly observable at room temperature. 

Energy Levels for Internal and Over-All Rotation of Two-Top Molecules. I. Microwave Spectrum of Dimethyl Silane. J. chem. Physics 34, 498-506 (1961). 

Diethynyl(dimethyl)silane, Me2Si(C C-H)2 47, reacts slowly at 80-90 °C with BEt3 to give the silole 48 which, however, undergoes fast various [4-1-2] cycloadditions (see Section 3.17.4.3.1) <2002ZNB741>. 

Alkyl Silanes or Alkyl Silicanes are compds combining alkyl groups with silicon or silicon hydrides, eg, methylsilaneCHjSiH, dimethyl silane (CH,),SiH, trimethyl silane (CH,),SiH, tetramethylsilane (CH,)4Si and yinylsilane (CH, CH)SiH,. They are very... 

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