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Organolithium reactions

The use of the Grignard reaction to synthesize 1-C-substituted carbohydrate derivatives from peracetylated glycosyl halides was introduced in 1945 by Hurd and Bonner.39 This reaction gives more homogeneous products in much better yields than the organolithium reaction. However, the product isomeric at C-l is generally produced simultaneously to a greater or lesser extent. [Pg.241]

While attempts were made to prepare the ethoxysilanes via the classic Grignard reaction, only phenyldimethylethyoxysilane was prepared in this manner. The Grignard reaction proved to be unsuitable for the preparation of the four para-substitutcd phenyldimethylethoxysilanes either because of sensitivity to Grignard formation or difficulty in isolating the product from the reaction mixture since the by-product salts were unfilterable. Therefore, all four silanes (p-chlorophenyl, p-methoxyphenyl, p-tolyl and p-trifluoromethylphenyldimethyl-ethoxysilane) were prepared via an organolithium reaction. [Pg.166]

It is necessary to protect any carboxylic acids present when carrying out organolithium reactions since one equivalent of the organolithium reagent would be wasted in an acid-base reaction with the carboxylic acid. [Pg.186]

Sparteine is the most important chiral ligand for lithium, and will be discussed in greater detail in chapters 5 and 6. However, irrespective of its chirality, it is included in this list as it often leads to important enhancements of reactivity even when enantioselectivity is not required.15 (-)-Sparteine can also make a very suitable replacement for toxic HMPA.16 Another class of ligand yet to be exploited are terminal alkenes, which appear to be able to affect the outcome and selectivity of certain organolithium reactions,17 perhaps by forming a Li—1 complex.18... [Pg.5]

Scheme 6.2.4 summarises the possible mechanisms by which (-)-sparteine induces asymmetry into organolithium reactions, highlighting organolithiums whose reactions typify of each type of asymmetric induction. [Pg.268]

Summary Starting with poiy(dichlorosilyiene-co-methylene) the synthesis of new poly(di-alky silylene-co-methylenes), poly(dialkenylsilylene-co-methylenes), and poly(dialkinylsilyl-ene-co-methylenes) was achieved by Grignaid or organolithium reactions. Furthermore poly(dichlorosilylene-co-methylene) was photochlorinated under UV irradiation to poly-(dichlorosilylene-co-dichloromethylene). [Pg.733]

Diethoxymethane (DEM), an acetal with solubility similar to etheric solvents, may be a good substitute forTHF and EtzO [14]. DEM has a low propensity to form peroxides and can be used for Grignard reactions and organolithium reactions. Methyl lithium is available as a solution in DEM, which is much safer than CH3Li solutions in Et20 [15]. [Pg.88]

To assess the stereospecificity of the Grignard and organolithium reactions with menthyl phosphinates, the diastereomeric purity of starting menthyl esters was estimated by pmr spectroscopy (see Sect. 2.2) and, in most cases, highest reported rotations were used to estimate the. enantiomeric purity of the derived optically active phosphine oxides The method of preference for determining the enantiomeric purity of a phosphine oxide, even in those cases in which a value for the rotation of optically pure material is reported, involves stereospecific reduction of the phosphine oxide with hexa-chlorodisilane (see Sect. 2.4) to the corresponding phosphine, followed by quatemization with 2-phenyl-2-methoxy-ethyl bromide and pmr analysis of the diastereomeric phosphonium bromides (Eq. (1)) > This method for determining optical purity, shown ) to be applicable... [Pg.64]

Typical solvents used for organolithium reactions include THF, diethyl ether (ether), dimethoxyethane, toluene, and hexane. Although THF and diethyl ether are the most common solvents involving organolithium reagents, one should be aware that both... [Pg.32]

A long-standing reaction is the oxidation of aryl boronic acids to phenols by alkaline peroxide, usually in the work-up of a borate-organolithium reaction, without isolation of the boronic acid, i.e. an efficient ArBr ArOH conversion. A variant under milder conditions uses sodium perborate (for the conversion of 5-bromopyrimidines), and, using oxone, oxindoles can be prepared from 1-Boc indoles via direct... [Pg.52]

Reaction conditions are given in the experimental section. Yields vary considerably, but most of the normal organolithium reactions occur in satisfactory-to-good yields. When readily enolizable protons are present, lower yields might be expected and were found—as with cyclo-pentanone. Buhler, in a recent optimization study, found the yield of the tertiary alcohols from cyclopentanone, cyclohexanone, and benzo-... [Pg.45]


See other pages where Organolithium reactions is mentioned: [Pg.263]    [Pg.325]    [Pg.210]    [Pg.185]    [Pg.1]    [Pg.1]    [Pg.4]    [Pg.214]    [Pg.226]    [Pg.258]    [Pg.258]    [Pg.261]    [Pg.273]    [Pg.328]    [Pg.286]    [Pg.8]    [Pg.164]    [Pg.329]    [Pg.244]    [Pg.1484]    [Pg.329]    [Pg.760]    [Pg.268]    [Pg.8]    [Pg.150]    [Pg.150]    [Pg.151]    [Pg.35]    [Pg.45]    [Pg.208]   


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Aldehydes reaction with organolithium compounds

Aldehydes reaction with organolithium reagents

Alkenes, reaction with organolithium reagents

Alkynes, reaction with organolithium reagents

Amide, sodium reactions with organolithium

Amides reaction with organolithium reagents

Anisole reaction with organolithium

Benzothiazole, 2-vinyladdition reactions with organolithium compounds

Boron trifluoride organolithium reactions

Boronic esters reaction with organolithium reagents

Carbon dioxide, reaction with organolithium reagents

Carbon monoxide, reaction with organolithium compounds

Carbonyl compounds, reactions with organolithiums or Grignard reagents

Carbonylation organolithium tandem reactions

Carboxylic acids reaction with organolithium compounds

Carboxylic acids reaction with organolithium reagents

Conjugate addition reactions organolithium reagents

Diketones reaction with organolithium

Diols reaction with organolithium reagents

Enol acetates, reaction with organolithium reactions

Esters reaction with organolithium compounds

Esters reaction with organolithium reagents

Ethers reaction with organolithium reagents

Ethers, silyl enol reaction with organolithium

Halides palladium-catalyzed reaction with organolithium compounds

Halides reaction with organolithium reagents

Halides, alkyl, reaction with organolithium reagents

Halides, vinyl reaction with organolithium

Heterocycles reaction with organolithium reagents

Hydrazones reaction with organolithium

Imine organolithium reaction

Intermediates organolithium reactions

Intramolecular carbolithiation reactions organolithium intermediates

Ketones reaction with organolithium compounds

Ketones, chiral reaction with organolithium

Ketones, reaction with organolithium reagents

Lithium carboxylates, reaction with organolithiums

Methanol, reaction with organolithium

Methanol, reaction with organolithium reagents

Naphthylimine, N-cyclohexyladdition reactions with organolithium compounds

Nitriles, reaction with organolithium reagents

Nitrogen reaction with organolithium

Organolithium compounds addition reactions

Organolithium compounds carbonyl compound reactions

Organolithium compounds reactions with halides

Organolithium compounds rearrangement reactions

Organolithium compounds, exchange reactions

Organolithium compounds, reaction mechanisms

Organolithium compounds, reactions

Organolithium compounds, reactions with dienes

Organolithium compounds, reactions with enynes

Organolithium reagents addition reactions

Organolithium reagents coupling reactions

Organolithium reagents nucleophilic addition reactions

Organolithium reagents reaction

Organolithium reagents reaction with acid chlorides

Organolithium reagents reaction with epoxides

Organolithium reagents reaction with oxiranes

Organolithium reagents reactions with acetals

Organolithium reagents reactions with carbonyl compounds

Organolithium reagents, reaction with amines

Organolithium reagents, reaction with chiral ketones

Organolithium reagents, reaction with conjugated carbonyls

Organolithium reagents, reaction with diketones

Organolithium reagents, reaction with enol acetates

Organolithium reagents, reaction with hindered ketones

Organolithium reagents, reaction with hydrazones

Organolithium reagents, reaction with oximes

Organolithium reagents, reaction with phosphonium salts

Organolithium reagents, reaction with sulfides

Organolithium reagents, reaction with sulfones

Organolithium reagents, reaction with sulfoxides

Organolithium reagents, reaction with vinyl ethers

Organolithium stereoselective reactions

Organolithium synthetic reaction

Organolithiums carbanion reactions

Organolithiums formylation reactions

Organolithiums reaction with acetone

Organolithiums reaction with carbonyl compounds

Organolithiums reaction with esters to form tertiary

Organolithiums reaction with water

Organolithiums transmetalation reactions

Other Reactions of Organolithiums

Oxazolines reaction with organolithium

Oxazolines reaction with organolithium reagents

Oxetanes reaction with organolithium reagents

Oximes reaction with organolithium

Oxygen reaction with organolithium reagents

Palladium, tetrakis catalyst coupling reactions between organolithium and

Peterson reaction, organolithium reagents

Phenoxide, bis(2,6-di-r-butyl-4-methylmethylaluminum complex reactions of organolithium compounds

Phosphonium salts reactions with organolithiums

Polymeric organolithium compounds branching reactions

Pyridazine reactions with organolithiums

Pyridine reaction with organolithium reagents

Pyridine reaction with organolithiums

Pyrimidine, reaction with organolithiums

Reaction with Grignard and organolithium

Reaction with Grignard and organolithium reagents

Reaction with organolithium

Reaction with organolithium compounds

Reaction with organolithium reagents

Reactions of Epoxides with Grignard and Organolithium Reagents

Reactions of Organolithiums with Carbonyl Compounds

Reactions of Organomagnesium and Organolithium Compounds

Reduction reaction with organolithium compounds

Stannanes reaction with organolithium compounds

Stereoselectivity in Organolithium Reactions

Stereoselectivity organolithium tandem reactions

Styrenes reactions with organolithiums

Subject reactions with organolithium reagents

Substitution reactions organolithium compounds with

Sulfones reaction with organolithium

Sulfur, reaction with organolithium compounds

Synthesis reaction with organolithium compounds

Tandem reactions organolithium synthetic intermediates

Tosylhydrazones reaction with organolithium

Tosylhydrazones reaction with organolithium reagents

Transition metal halides reactions with organolithium compounds

Triazines reactions with organolithiums

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