Chloro dimethylsilane

A simple example involves the reaction of the silyl ether 213, made from the corresponding 4-hydroxy-alkene by treatment with (bromomethyl)chloro-dimethylsilane, with tributyltin hydride and a radical initiator. Bromine abstraction and intramolecular cyclization with the double bond leads to the bicyclic 214, which upon oxidation with hydrogen peroxide gives the branched-chain 215 in an overall yield of 73% from the alcohol precursor of 213 (Scheme 21). When the sequence is conducted with the C-4 epimeric starting alcohol, the final product again has the hydroxymethyl group cis-related to the hydroxy group.217... 

Silylmethyl radical cyclizations are a related class of reactions in which the heterocycle serves a temporary purpose to direct the introduction of a methyl or hydroxymethyl group adjacent to the hydroxy group. Starting from the optically active allylic decalin alcohol, reaction with bromomethyl(chloro)dimethylsilane gives the a-bromosilyl ether. Treatment with tributyltin hydride affords the stereoselective cyclization to a five-membered siloxane62. The siloxane ring is converted either to the a.r-dihydroxy compound, or to the ot-methylated derivative63. 

AUyl(chloro)dimethylsilane (25 9.7 g, 70 mmol), BrCHaCl (9.3g, 70 mmol) and diy THF (150 ml) were added to a 500-mL three-necked flask equipped with a magnetic stirrer bar, N2 inlet tube, and thermometer. The mixture was cooled to -70 °C and 1.6 M Buli in hexanes (45 mL, 70 mmol) added down the cold wall of the flask via a syringe over 40 min. During the addition the temperature of the mixture was maintained between -70 and -60 °C. The soln was then warmed to rt and H2O (50 mL) was added. The mixture was extracted with hexanes (3 x 100 mL). The combined extracts were dried (CaCy and evaporated under reduced pressure. The residue was distilled to give the a-diloromethylsilane 26 yield 7.6 g (71%) bp 77°C/80Torr. 

The electrophilic reactivity of silicon in (bromomethyl)chloro-dimethylsilane has also served in a large number of applications concerning the surface modification of various silica gel or silicates derivatives. Indeed, haloaUcyl-activated silica supports are promising for the preparation of stationary phases (sorhents) with high loadings of immohilized ligands. ... 

Of many Lewis acid catalysts, indium(III) complexes have been demonstrated to perform unique catalysis, allowing allylation of carbonyls followed by substitution of the resulting hydroxy group by chlorine derived from the starting allyl(chloro)dimethylsilane and direct chlorination of the resulting secondary alcohols (Schemes 3-163 and 3-164). ... 

S 2 bimolecular nucleophilic TBSCl /cr/-butyl(chloro)dimethylsilane... 

The course of this reaction is analogous to that of the corresponding reactions with simple silanes such as (chloromethyl)aryl dimethylsilanes (16) and (chloro- or iodomethyl) dimethylsilanes (93), although in these it is aryl or hydride migration that leads to rearrangement. 

In 1993 Uozumi et al. reported on the regio- and enantioselective hydrosilylation of styrene derivatives using an optically active palladium catalyst [1]. In the context of these examinations the authors also mentioned the reaction of indene with trichlorosilane in all cases the 1-substituted products only were got no further characterization was given, however. In accordance with these results, our investigations on the hydrosilylation of indene with trichlorosilane, chlorodimethyl-silane, and dichloromethylsilane in the presence of Speier s catalyst showed the same addition tendencies by distillation we isolated in high yields trichloro(l-indanyl)silane (la), dichloro(l-in-danyl)methylsilane (lb), and chloro(l-indanyl)dimethylsilane (Ic), respectively (Scheme 1). 

Chloromethyl) isocyanatodimethyhilane 504, triethylisocyanatosilane 508, and various silane diisoqranates were prepared by heating chloro(chloromethyl)dimethylsilane or dichlorodialkyl silanes with urea in the presence of SnCU or hexamethyldisila-zane for 5-6 h at 115-125 °C [356]. 

Generation of ChIoro(lithiomethyl)dimethylsilane. Treatment of (bromomethyl)chlorodimethylsilane in THF/ether with 1 equiv of n-butyllithium in hexanes at — 120°C produces chloro (lithiomethyl)dimethylsilane. This lithiated derivative spontaneously eliminates LiCl to give an intermediate silaethylene species, which undergoes dimerization to afford 1,1,3,3-tetramethyl-1,3-disilacyclobutane (45%), together with a small amount of l,l,3,3,5,5-hexamethyl-l,3,5-trisilacyclohexane (15%) (eq9). ... 

Preparative Methods can be prepared either by the reaction of phenylmagnesium bromide with chloro(chloromethyl)di-methylsilane in ether at reflux, or by the reaction of phenylmagnesium bromide with chloro(chloromethyl)dimethylsilane in the presence of catalytic (Al,Al,lY,iV -tetramethylethylenedi-amine)zinc in 1,4-dioxane at 20 °C ... 

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