Trimethylsilylmethyl lithium

To a solution of trimethylsilylmethyl lithium (from chloromethyltrimethyl-silane (15.8mmoI) and lithium dispersion (196mmol)) in ether (30ml) was added cyclohexane carboxaldehyde (14.2 mmol) at ambient temperature, with stirring. After a further 10min at ambient temperature, the solution... 

Trimethylsilyhex-l-yne, 46 Trimcthylsilylmethyl cyclohexyl ketone, 78-9 Trimethylsilylmethyl lithium, 64,78,79... 

Enolate 18 was prepared by two different methods either by deprotonation of the corresponding lactone 20 or 21 by LDA (method A) or by 1,4-addition of bis(methylthio)trimethylsilylmethyl-lithium as a nucleophile to the lactone 22 (method B)63,64... 

Boileau and coworkers11 have used a novel trimethylsilylmethyl lithium initiator MesSiCTDLi (1), in combination with a cryptand [211], for the ring-opening polymerization of cyclosiloxanes. Initiation of hexamethylcyclotrisiloxane (D3) and octamethylcyclotetrasiloxane (D4) polymerization has been followed by H, 7Li, 13C and 29Si NMR. 

Amides Borane-Trimethylamine. Meth-oxy(phenylthio)trimethylsilylmethyl-lithium. 

Intermediate 113 was transformed into the trimethylsilyl methyl ketone 119 in quantitative yield via the acid chloride, followed by the addition of trimethylsilylmethyl lithium (Scheme 2.13). Subsequent Peterson olefination of aldehyde 108 with 119 resulted in the required unsaturated ketone 120 in 95% yield. Subsequent desilylation and thioester hydrolysis afforded a 97% of the seco acid 121. Lactonization was achieved in 32% yield via the phosphoric acid-mixed anhydride, however this procedure also formed about 25% of the dimeric bis lactone. Following removal of the acetonide under the action of acid, a nonselective oxidation with RuCl2(Ph3P)3 produced a 1 1 mixture of the natural... 

Ytterbium(lll) tris(perfluoroalkanesulfonyl)methides 34 are effective catalysts (10% mol) for the Friedel-Crafts acylation of arenes with anhydrides. Compounds 34 can be prepared as described in Scheme 3.7. Trimethylsilylmethyl lithium 31 is reacted with commercially available per-fluoroalkanesulfonyl fluorides, giving intermediates 32 that can similarly produce tris-perfluoroalkanesulfonyl derivatives 33. These compounds are converted into the catalysts 34 by reaction with ytterbium oxide. It is shown that the highly fluorinated catalyst (34, Ri = C5F13, = C8F17) (10% mol)... 

Wilkinson and coworkers obtained stable alkyl complexes by the reaction of transition metal halides or complex halides with trimethylsilylmethyl lithium 72 With these alkyl complexes, no /3-elimination reaction proceeds. The action of Grignard or organolithium reagents on halogen complexes of Pt(II) and Pd (II) has been widely used for the preparation of alkyl complexes, and quite stable alkyl complexes of noble metals can be prepared 73K... 

Alternatively, secondary and tertiary carboxylic acid methyl or ethyl esters react (6) with two equivalents of trimethylsilylmethyl lithium (prepared in pentane) to give /2-ketosilancs in good (80-96%) yield. Primary esters also give / -ketosilanes, but in lower (45%) yield. 

Methoxy(phenylthio)methyl]1ithium (94) and [methoxy(phenylthio)-trimethylsilylmethyl]lithium (95) react in a 1,2-sense with ot, 0-unsaturated aldehydes and ketones to give 0,S-acetals and... 

A highly convenient method of generating trimethylsilylmethyl-lithium, a reagent for methylenation (Peterson olefination) of ketones and aldehydes, has been discovered. Transmetallation between the readily available (trimethylsilyl-methyl)tributyltin and n-butyl-lithium in a mixture of hexane and THF furnishes the reagent in quantitative yield at 0 °C in 30 min. ... 

Kwan and Battiste have employed the Peterson protocol to synthesize vinylsilanes 39/40 in a one-pot process. The procedure involved the addition of trimethylsilylmethyl lithium to non-enolizable aromatic ketones followed by addition of diethylaluminium chloride, then water. The tabulated examples illustrate the rare use of organoaluminum reagents to promote elimination. Good chemo- and stereoselectivity was observed. 

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