Allyltrimethylsilane lithium

Lithium diallylcuprate, 11 Lithium dibutylcuprate, 61 Lithium dimethylcuprate, 63, 258 Sakurai reaction Alkylaluminum halides, 5 Allyltrimethylsilane, 11, 305 Titanium(IV) chloride, 304 with other organometallic agents (IS, 2S) -2-Amino-3-methoxy-1 -pheny 1-1-propanol, 17... 

Triphenylphosphine-Diethyl azodicar-boxylate, 332 Other substitutions Allyltrimethylsilane, 11 Benzylamine, 79 Bromodimethylborane, 47 Chlorotrimethylsilane-Lithium, 81 Crotyltrimethylsilane, 86 Diethylzinc-Titanium(IV) chloride, 21 Lithium bis(dimethylphenylsily 1)-cuprate, 161... 

Allyltributyltin, 10 Vinyltrimethylsilane, 343 Homoallylic ethers Allyltrimethylsilane, 11 Crotyltrimethylsilane, 86 Trityl perchlorate, 339 Homopropargylic alcohols Allenylboronic acid, 36 D imethoxy [ 1 -trimethylsilyl-1,2-buta-dienyljborane, 218 Lithium acetylide, 44 Triisopropoxy[l-(trimethylsilyl)-l,2-buta-dienyl]titanium, 218 Hydroperoxides Oxygen, singlet, 228 Hydroxy acids a-Hydroxy acids... 

Lithium-Ammonia, 158 Potassium hydride, 257 Tetrakis(triphenylphosphine)palla-dium(O), 289 Tributyltin chloride, 315 8,e-Unsaturated aldehydes and ketones Allyltrimethylsilane, 11 Lead tetraacetate, 155 Unsaturated amides Bis(benzonitrile)dichloropalladium(II), 34... 

Aluminum ate complexes, (CH3)3SiCH -CHCH2 Al(C2H5)3Li+ (1). The ate complex is prepared by reaction of the lithium anion of allyltrimethylsilane with A1(C2Hs)3. In contrast with the anion of allyltrimethylsilane, which reacts with carbonyl compounds mainly at the y-position, 1 reacts selectively at the a-position (equation T). 

The reaction of (S)-phenylglycinol-derived oxazolidines 215 with allyltrimethylsilane and propynyltrimethylsilane lithium reagents, afforded 3-aminoalcohols with a vinylsilane or alkynylsilane appendage 216 and 217. The same reaction, performed in the presence of Ti(OiPr)4 gave allylsilane and allenylsilane derivatives 218 and 219 <02JOC1496>. 

Conjugate addition to acyclic Michael acceptors. Sakurai and Hosomi (9, 445-446) reported one example of the fluoride ion-catalyzed reaction of allyltrimethylsilane with an acyclic enone. In that case (reaction with C6H5CH=CHCOCH,). 1.2- and 1,4-adducts are obtained in the ratio 2 1.1,4-Addition is enhanced by use of DMF and HMPT as solvent and by increase in the size of the group adjacent to the carbonyl group. 1,4-Addition is the main or predominant reaction with a,3-unsaturated esters or nitriles. In this case, it is superior to or competitive with allylation with lithium diallylcuprate. Yields in 1,4-additions to a,p-enones can compare favorably with those obtained with reactions catalyzed by TiC. ... 

Reaction with Alkyl Halides, Epoxides, and Other Electrophiles. TrimethylsUylallyllithium reacts with alkyl halides at low temperature, giving mixtures of a- and y-(E) products in ratios that vary with the electrophile and the reaction conditions (eq 9). In these reactions the )/-(E)-alkylation product generally predominates. For example, when trimethylsilylaUyl-lithium is formed by deprotonation of allyltrimethylsilane with n-butyllithium in the presence of potassium r-butoxide in THF, the (E)-vinylsilane alkylation product is obtained in better then... 

Tri-0-benzyl- e-D-ribofuranosyl acetate with allyltrimethylsilane and the trimethylsilyl enol ether of acetophenone, together with tin(IV) tetrachloride, tin(II) triflate and lithium perchlorate, gave only the a-c-glycosides (93) and (94), respectively, and the radioactively labelled selenazolecarboxylate (95) has been elaborated from 2,3,5-tri-Q-benzoyl- -D-ribofuranosyl acetate by way of the labelled glycosyl... 

The regioselectivity of nucleophilic attack for the formation of G-G bonds depends on the nature of the nucleophile as well as the substituents attached to the dienyl ligand. Reactions of 1,2-disubstituted 42a and 42b and 1,4-disubstituted 43a and 43b cations with methanol, triphenylphosphine, lithium dimethylcuprate, and sodium dimethylmalonate nucleophiles have been investigated. It was found that cations 42a and 42b direct nucleophilic attack regiospecifically to the unsubstituted C5 position whereas cations 43a and 43b undergo G1 addition, although in a less predictable manner (Scheme 3). Weak nucleophiles such as methanol, allyltrimethylsilane, furan, and allylic organozirconiums are found to attack exclusively at the less substituted pentadienyl terminus and on the less stable, but more reactive, transoid form. Malonate anion attack on 1-substituted acyclic (77 -pentadienyl)-... 

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