Tris trimethylsilyl aluminum

Colvin, E. W. Silicon Reagents in Organic Synthesis-, Academic Press Inc. San Diego, CA, 1988. 

Manoso, A. S., PhD dissertation. University ofMaryland,2004,andcited references. 

Hamdouchi, C. Jaramillo, C. Lopez-Prados, J. Rubio, A., Tetrahedron 

Okamuia, K. Dale, T. Mori, M., Tetrahedron Lett. 

Solubility sol ethers, pentane, benzene reacts violently with pro-tic solvents. 

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The silylation of allylic acetates has been accomplished utilizing tris(trimethylsilyl)aluminum and Pd° catalysts. The stereochemistry of this reaction has been determined and is consistent with exclusive ligand addition (equation 198)225... 

Tris(trimethylsilyl)aluminum reacts with ir-allylpalladium complexes to yield allylsilanes. The regio-chemistry of this addition is highly dependent on reaction conditions, and no trends can be readily discerned.225... 

Scheme 3. Key a) Tris(trimethylsilyl) aluminum etherate, Et20, -78 °C then Ac20, DMAP, to 23 °C b) 2LiNEt2, THF, -78 °C then 23 °C c) 2LDA, THF, 50 °C then CH3I, -78 °C d) 4LiNEt2, THF, -78 °C to 50 °C, then CH3I, -78 °C e) O3/O2, CH2CI2, -78 °C then SiC>2 followed by aq. 3M H2SO4.

In aryl and vinyl bromides and iodides, silylation has been performed by reaction with tris(trimethylsilyl)aluminum etherate in the presence of a nickel(II) chloride-triphenylphosphine complex381. In vinyl iodides the alkene stereochemistry is retained but it is lost in bromides. 

Tris(trimethylsilyl)aluminum, AllSifCHOj] (1). The reagent is obtained as the THE complex by reaction of Hg(Si(CH,),]i with aluminum powder in THE (90% yield). Nonsolvated reagent is prepared by reaction of sodium tetrakis(trimethylsilyl)aluminate with AlCl, in pentane. It ignites spontaneously in air dec. at 50°."... 

For example, when acyclic enones are exposed to tris(trimethylsilyl)aluminum (7) at room temperature, only the 1,2-addition product is observed, whereas the addition proceeds via a 1,4-addition process when the reaction is conducted at -78 C (compare entries 8 and 9 in Table 5). In contrast, a, -unsatu-rated aldehyde substrates only undergo 1,2-additions with reagent (7). 

Acylsilanes may be prepared directly from either acyl chlorides or anhydrides by treatment with tris(trimethylsilyl)aluminum-ate complexes (equation 24). ... 

The silyl organoaluminum reagent (52) was prepared either by the addition of activated aluminum to a tetrahydrofuran solution of chlorotrimethylsilane, or by the treatment of sodium tetrakis(trimethyl-silyl)aluminate with aluminum chloride. Alternatively, ate complex (53) may be prepared by the addition of methyllithium to tris(trimethylsilyl)aluminum. ... 

Allyl acetates are readily converted to allylsilanes in good yields, when they are reacted with 0.5 equiv of tris(trimethylsilyl)aluminum etherate and 4-6 mol % of Pd(PPh3)4 in THF at 0-25 °C (Scheme 34).For the reaction with unsynunetrical allyl acetates, the trimethylsilyl group tends to attack the more substituted carbon of the allyUc system under Pd-catalyzed conditions. With 10 mol % of Mo(CO)e (toluene reflux for 2.5 h), on the other hand, the trimethylsilyl group selectively attacks the less substituted carbon as exemplified by the exclusive formation of geranyl(trimethyl)silane in 65% yield. Under the Pd-catalyzed conditions, many functional groups of synthetic importance (e.g., vinyl bromide, acetals, esters, and enones) remain intact. 

There are several alternative methods for the formation of acylsilanes these include the reaction of silyl cuprates with acid halides, palladium-assisted coupling of acyl halides with hexamethyldisilane, the reaction of thiopyridyl esters with tris(trimethylsilyl)aluminum in the presence of Cu salts, and the hydroboration of trimethylsilyl-substituted alkynes. While all of these procedures are complementary, the method involving the title corqtound provides an easy, inexpensive route to acylsilanes. 

TMS, TMS, TMS A1 Tris(trimethylsilyl)aluminum Tris(trimethylsilyl)aluminum-Ethyl Ether Complex 65343-66-0 75441-10-0 745... 

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