Silane, lithium complex

CtH,ftN4, 1,2-Ethanediamine, N,N,N, N -te-tramethyl-, lithium complex, 26 148 C Hi Si, Silane, triethyl-, ruthenium complex, 26 269... 

C5H15O3P, Triethyl phosphite, iron complex, 26 61, 28 171 nickel complexes, 28 101, 104-106 CjHijP, Phosphine, triethyl-, gold-osmium complexes, 27 209, 211 gold-platinum complex, 27 218 nickel complex, 28 101 platinum complexes, 26 126, 135-140, 27 32, 34,28 27, 120, 122, 133, 29 191 C5H16N4, l,2-Ethanediamine,AfJVJV Af -tetramethyl-, lithium complex, 26 148 CjH,6P2, Phosphine, l,2-ethanediylbis(di-methyl-, nickel complex, 28 101 CjHijSi, Silane, triethyl-, ruthenium complex, 26 269... 

A solution of 100 g (0.61 mole) of trimethyl(phenylmethyl)silane [Pfalz and Bauer] and 87.5 mL (0.61 mole) of AI,yV,yV, (V -tetramethyl-l,2-ethanediamine (TMEDA) [Aldrich] dissolved in 150 mL of diethyl ether is placed in a 1-L three-necked flask provided with a dropping funnel, a mercury relief valve, and a magnetic stirrer. This solution is cooled to — 20°, and 364.3 mL (0.61 mole) of a. f> M solution of butyllithium in hexane is added over a 90-min period. After being warmed to room temperature, the reaction mixture is stirred for at least 6.5 hr while the orange-yellow lithium complex salt precipitates. The mixture is cooled to -20°, and a solution of 92.7 g (0.61 mole) of N,N,N, N -tetramethylphosphorodiamidous chloride [Alfa Products] in 80 mL of diethyl ether is added over a period of 90 min. This mixture is allowed to warm to ambient temperature and is stirred for 1 hr. Then the LiCl is Altered and washed... 

The THF-containing complexes formed between trinitrobenzene and the lithium or potassium salts of trimethyl-, triethyl- or triphenyl-germanate, -silanate or -stannate decompose explosively on heating, though trinitrobenzene-potassium trimethyl-stannate decomposes explosively at ambient temperature. 

The 10-57-5-hydridosiliconate ion 62 is known in association with lithium,323 tetrabutylammonium,101 and bis(phosphoranyl)iminium93 cations. It is synthesized by hydride addition to the 8-.S7-4-silane 63, which is derived from hexafluoroacetone.101 Benzaldehyde and related aryl aldehydes are reduced by solutions of 62 in dichloromethane at room temperature101 or in tetrahydrofuran at 0°96 within two hours. The alkyl aldehyde, 1-nonanal, is also reduced by 62 in tetrahydrofuran at O0.96 Good to excellent yields of the respective alcohols are obtained following hydrolytic workup. The reactions are not accelerated by addition of excess lithium chloride,96 but neutral 63 catalyzes the reaction, apparently through complexation of its silicon center with the carbonyl oxygen prior to delivery of hydride from 62.101... 

The reactive species in fluoride-mediated carbon-carbon bond-forming reactions has been investigated.146 The regio- and diastereo-selectivities of silanes reacting with cyclohexenone in the presence of a catalytic amount of fluoride have been compared with the reactivity of analogous solvent-separated lithium ion pairs. Closely analogous behaviour has been observed, showing that carbanions and not siliconate complexes are the reactive species in the fluoride-catalysed reactions. 

Acyl anions (RC(=0)M) are unstable, and quickly dimerize at temperatures >-100 °C (Section 5.4.7). These intermediates are best generated by reaction of organolithium compounds or cuprates with carbon monoxide at -110 °C and should be trapped immediately by an electrophile [344—347]. Metalated formic acid esters (R0C(=0)M) have been generated as intermediates by treatment of alcoholates with carbon monoxide, and can either be protonated to yield formic acid esters, or left to rearrange to carboxylates (R0C(=0)M —> RC02M) (Scheme 5.38) [348]. Related intermediates are presumably also formed by treatment of alcohols with formamide acetals (Scheme 5.38) [349]. More stable than acyl lithium compounds are acyl silanes or transition metal acyl complexes, which can also be used to perform nucleophilic acylations [350],... 

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