Trimethylsilyl lithium

A solution of trimethylsilyl lithium (10 mmol) in HMPA (CAUTION— CANCER SUSPECT AGENT) (5 ml) and ether (10 ml, from the MeLi) prepared as above was cooled to 0°C and diluted with THF (20 ml). Copper(i) cyanide (5 mmol) was added in one portion, and the resulting black mixture was stirred at 0°C for 20min. 

Trimethylsilyl enol ethers, 94,133 Trimethylsilyl ketene acetals, 112-113 3-Trimethylsilyl -lactam, 71 Trimethylsilyl lithium, 51-2... 

The reactions of a benzylzinc chloride TMEDA adduct with either benzyllithium or benzyl(trimethylsilyl)lithium TMEDA adduct yielded both homoleptic dibenzylzinc (37, Figure 16) and heteroleptic monobenzylzinc compounds as TMEDA adducts. The heteroleptic diorganozinc compounds do not disproportionate as long as TMEDA is present, but removal of the chelating nitrogen ligand in the gas phase does cause disproportionation. 

Lithium bis(trimethylsilyl)amide (LiHMDS) Disilazane, 1,1,1,3,3,3-hexamethyl-, lithium salt (8) Silanamine, 1,1,1 -trimethyl-N-(trimethylsilyl)-, lithium salt (9) (4039-32-1)... 

Contrary to the tin series, transmetallation reaction with alkyl- or arylgermanium trichloride starting from zirconaindenes does not give monochloro 1-germaindene in good yield103. However, the required compounds were synthesized from 1,1-dichloro-1-germaindenes, by reaction of phenyl- or silyl-tris(trimethylsilyl)lithium (Scheme 18). 

Thus, if trimethylsilyl anion were used as the nucleophile, then requisite diastereomer 30 could become available. Of the various counterions, Li+, Na+, and K+ have been examined by others. None of these species were suitable for direct 1,2-addition to carbonyl compounds. For example, trimethylsilyl lithium (Me3SiLi) adds nicely 1,4- to enones by a one-electron-transfer process, but does not provide a-silyl alcohols from ketones or aldehydes. In contrast tris(trimethylsilyl)alumi-... 

When bright yellow, solid bis(trimethylsilyl)mercury is treated with trimethylsilyl-lithium in 1,2-dimethoxy ethane (DME), color changes occur and either a three- or a four-coordinated anionic silyl-Hg compound may be isolated according to the stoichiometry ... 

Treatment of -caprolactone with 7V,7V-bis(trimethylsilyl)lithium amide and then with A-phenyl triflimide affords 2-triflyloxy-2-hexenolide (22). The latter is obtained in 89% yield <89CL1313> and can be regarded as a key intermediate in the syntheses of diverse 2-substituted 4,5,6,7-tetra-hydrooxepines. For instance, reactions of (22) with lithium dialkyl- or diphenylcuprates result in 2-butyl-substituted derivatives (23 R = Aik, Ph) <89CL1313>, while analogous interaction with hexa-methyldistannane gives 2-trimethylstannyl-4,5,6,7-tetrahydrooxepin (23 R = SnMcj) <91SL197>. 

CgH,gLiPSi2 20C4Hs, Phosphide, bis(trimethylsilyl)-, lithium, -2-tetrahydrofuran, 27 243, 248... 

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