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Chloromethyltrimethylsilane

The present procedure provides a convenient two-step route to 2-(hydroxy-methylJallyltrimethylsilane using relatively inexpensive reagents. Other approaches require more steps and expensive chloromethyltrimethylsilane. ... [Pg.65]

A solution of s-BuLi (1.05 mmol, 1.1 m in cyclohexane) was added dropwise to a stirred solution of chloromethyltrimethylsilane (lmmol) in THF (to give a 1 m solution of reagent) at -78 °C. After 5 min, TMEDA (1.05 mmol) was added, and the stirred solution was allowed to warm to -55 °C over 0.5 h, by which time it was pale yellow (the presence of TMEDA increases the rate of formation of the reagent, but has no other advantages). [Pg.21]

The parent alcohol can be obtained in a straightforward manner from chloromethyltrimethylsilane (Chapter 16). The protection afforded is naturally related to the functionality involved, and liberation is achieved using either fluoride ion or a Lewis acid. For example, 2-trimethylsilylethyl esters (Chapter 16) are stable to a wide variety of conditions such as those used in peptide synthesis, but are readily cleaved by fluoride ion (14,15). [Pg.46]

A mixture of Mg (0.163 g atom) and chloromethyltrimethylsilane (0.163 mol) in ether (90 ml) was heated gently (air-gun) to initiate reaction (once started, the reaction can be very exothermic, and it should be cooled occasionally to maintain a gentle reflux). When all the Mg had dissolved, paraformaldehyde (5g, 0.166mol of CH20) was added, and reflux was continued for a further 2.25 h. The cooled mixture was diluted with ether, and washed with saturated ammonium chloride solution. The aqueous layer was re-extracted with ether, and the combined ethereal extracts were dried and concentrated. Distillation gave 2-trimethylsilylethanol (0.156mol, 96%), b.p. 34-35°C/1 mmHg. [Pg.71]

The Grignard reagent prepared from chloromethyltrimethylsilane (30 mmol) and Mg (36 mg atom) in ether (20 ml) was added dropwise to diphenyl phosphorazidate (27 mmol) in ether (40 ml), keeping the temperature below 0°C. The reaction mixture was stirred for 2 hat 0 C, and then at ambient temperature for 3 h. It was then cooled to 0 °C, and ice-water was added. The mixture was filtered, and the solid was washed with ether. The combined ethereal extracts were washed with ice-water and dried. Careful concentration at <45 °C/atmospheric pressure, then distillation at... [Pg.155]

Trialkylsilyl groups have a modest stabilizing effect on adjacent carbanions (see Part A, Section 3.4.2). Reaction of the carbanions with carbonyl compounds gives (3-hydroxyalkylsilanes. (3-Hydroxyalkylsilanes are converted to alkenes by either acid or base.270 These eliminations provide the basis for a synthesis of alkenes. The reaction is sometimes called the Peterson reaction.211 For example, the Grignard reagent derived from chloromethyltrimethylsilane adds to an aldehyde or ketone and the intermediate can be converted to a terminal alkene by acid or base.272... [Pg.171]

Trimethylsilylepoxides can be prepared by an addition-cyclization process. Reaction of chloromethyltrimethylsilane with sec-butyllithium at very low temperature gives an a-chloro lithium reagent that leads to an epoxide on reaction with an aldehyde or ketone.291... [Pg.182]

Reaction of lithiated allylbenzotriazole 452 with chloromethyltrimethylsilane yields silyl derivative 464 which can be further alkylated to give compound 465 (Scheme 76) <1999JOC1888>. Upon heating, product 465 is readily converted to diene 466 via vicinal elimination of benzotriazolyl and silyl substituents. Additions of lithiated silyl derivative 464 to carbonyl groups of aldehydes lead to alcohols 463 which readily eliminate benzotriazole and silane to furnish 2-(l-hydroxyalkyl)butadienes 466 (R1 = 1-hydroxyalkyl). [Pg.58]

Dienes can be obtained from silylallenes by protodesilylation using boron trifluo-ride-acetic acid complex (equation 29)62. Since silylallenes can be obtained by the reaction of propargyl acetate with cuprous reagent derived from chloromethyltrimethylsilane, this reaction sequence constitutes conversion of propargylic acetate to butadiene through one carbon homologation. [Pg.376]

Lithiated chloromethyltrimethylsilane is a remarkably stable carbenoid [69] and shows exceptional reactivity in insertions into the alkenyl—zirconium bonds of unsaturated zirconacycles. It is the only known carbenoid that will insert into zirconacyclopentadienes... [Pg.100]

The Peterson reaction utilizes a metal derivative of chloromethyltrimethylsilane and the yields are better than the Wittig reaction. The intermediate P-hydroxysilanes can undergo either cis or trans elimination depending on reagent choice. [Pg.196]

Chloromethyltrimethylsilane, obtained from Petrarch Systems Inc., was purified by distillation at 97 C under atmospheric pressure. [Pg.3]

Silylation (see also Protection of alcohols) (Bromomethyl)chlorodimethylsilane, 316 /-Butyldimethylchlorosilane, 92 Chloromethyldiphenylsilane, 74 Chloromethyltrimethylsilane, 76 Di-/-butylmethylsilyl trifluoromethanesul-fonate, 95... [Pg.374]

Cesium fluoride-Tetraalkoxysilanes, 69 Chlorodiisopropylsilane, 72 Chlorodimethylsilane, 73 Chlorodimethylthexylsilane, 74 Chlorodiphenylsilane, polymeric, 74 Chloromethyldiphenylsilane, 74 Chloromethyltrimethylsilane, 76 Chlorotriethylsilane, 165, 323 Chlorotrimethylsilane, 165, 168 Chlorotrimethylsilane-Lithium, 81 Chlorotrimethylsilane-Sodium iodide, 81... [Pg.412]

As a general mle, unless an anion-stabilizing group, such as phenyl, or a heteroatom such as sulfur is present, the alkylsilane is not readily deprotonated. The a-halosilane can be deprotonated but, unlike the readily available chloromethyltrimethylsilane, there are few general methods to this approach. Al-kyllithium reagents add to vinylsilanes ( ) to produce the carbanion (287). Silyl derivatives with heteroatoms, such as sulfur, selenium, silicon or tin, in the a-position (288) may be transmetallated (Scheme 41). Besides the difficulty in synthesizing the anion, alkene formation lacks specificity for simple di- and tri-alkyl-substituted alkenes. As a result, the Peterson reaction of an a-silyl carbanion with a carbonyl has found the greatest utility in the synthesis of methylene derivatives, (as discussed in Section 3.1.3), heterosubstituted alkenes and a,p-unsaturated esters, aldehydes and nitriles. [Pg.783]

Trimethylsilyldiazomethane (96), prepared in excellent yield from chloromethyltrimethylsilane, is now commercially available (Petrarch). Trimethylsilyldiazomethane is readily lithiated and alkylated (equation 40).Synthetic applications of the resultant silyldiazoalkanes (97) have not yet been extensively explored. These might, for instance, react smoothly with acid chlorides to give diazoketones (see Section 1.4.6.1). [Pg.121]

Reaction of bis(trimethylsilyl)acctylene with (iodomethyl)mercury(II) iodide and diphenylmer-cury gave a low yield (10%) of 1.2-bis(trirnethylsilyl)cyclopropenc as a clear oil which rcsinified on standing at ambient temperature.Addition of trimethylsilylcarbene, generated from chloromethyltrimethylsilane and lithium 2,2,6,6-tetramethylpipcridide occurred in 15% yield to give the cyclopropene 1 as an oil which was stable for about a month at ambient tempera-ture." - ... [Pg.2739]


See other pages where Chloromethyltrimethylsilane is mentioned: [Pg.126]    [Pg.809]    [Pg.52]    [Pg.132]    [Pg.120]    [Pg.249]    [Pg.76]    [Pg.271]    [Pg.64]    [Pg.67]    [Pg.118]    [Pg.118]    [Pg.4453]    [Pg.675]    [Pg.462]    [Pg.669]    [Pg.76]    [Pg.47]    [Pg.129]    [Pg.98]   
See also in sourсe #XX -- [ Pg.76 ]

See also in sourсe #XX -- [ Pg.118 ]

See also in sourсe #XX -- [ Pg.76 ]

See also in sourсe #XX -- [ Pg.7 , Pg.22 , Pg.63 , Pg.78 , Pg.121 , Pg.122 ]

See also in sourсe #XX -- [ Pg.70 , Pg.241 ]

See also in sourсe #XX -- [ Pg.635 ]




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Chloromethyltrimethylsilane, Grignard

Chloromethyltrimethylsilane, Grignard reagent from

Lithiated chloromethyltrimethylsilane

Silylation Chloromethyltrimethylsilane

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