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From sulfonate esters

Olefin formation by elimination from sulfonate esters, 331... [Pg.496]

Metal halide salts other than sodium iodide have been used sparsely to prepare halodeoxy sugars from sulfonate esters. Lithium chloride (107) and lithium bromide (33) have found limited application. Potassium fluoride (dihydrate) in absolute methanol has been used (51, 52) to introduce fluorine atoms in terminal positions of various D-glucose derivatives. The reaction is conducted in sealed tube systems and requires... [Pg.169]

When the base is hydroxide and the reaction is done in water, as in the preparation of 189, this reaction is known as the Schotten-Baumann reaction, after Carl Schotten (Germany 1853-1910) and Eugen Baumann (Germany 1846-1896). Just as amides are prepared from the reaction of carboxylic acid esters with amines or ammonia, so sulfonamides are prepared from sulfonate esters. An example is the reaction of ethyl butanesulfonate (190) with ammonia to give butanesulfonamide, 191. [Pg.988]

For the preparation of olefins from sulfonic esters see section 205 (Olefins from Halides and Sulfonates)... [Pg.498]

Enantiomerically pure allenylzinc and indium reagents are readily available through oxidative transmetallation of transient allenylpalladium intermediates derived from sulfonic esters of (/ )- or (5)-3-butyn-2-ol derivatives, such as 250. When these transmetaUations are conducted in the presence of aldehydes, anti homopropargylic alcohol adducts 251 are formed with high diastereoselectivity (Scheme 10.49). The preference for anti over syn adducts can be assigned to an unfavorable eclipsing interaction between the methyl group of allenyl moiety and the... [Pg.295]

Sulfonate esters are subject to the same limitations as alkyl halides Competition from elimination needs to be considered when planning a functional group transforma tion that requires an anionic nucleophile because tosylates undergo elimination reactions just as alkyl halides do... [Pg.353]

An advantage that sulfonate esters have over alkyl halides is that their prepara tion from alcohols does not involve any of the bonds to carbon The alcohol oxygen becomes the oxygen that connects the alkyl group to the sulfonyl group Thus the configuration of a sulfonate ester is exactly the same as that of the alcohol from which It was prepared If we wish to study the stereochemistry of nucleophilic substitution m an optically active substrate for example we know that a tosylate ester will have the same configuration and the same optical purity as the alcohol from which it was prepared... [Pg.353]

The reaction of alcohols with acyl chlorides is analogous to their reaction with p toluenesulfonyl chloride described earlier (Section 8 14 and Table 15 2) In those reactions a p toluene sulfonate ester was formed by displacement of chloride from the sulfonyl group by the oxygen of the alcohol Carboxylic esters arise by displacement of chlonde from a carbonyl group by the alcohol oxygen... [Pg.640]

If a waste sulfuric acid regeneration plant is not available, eg, as part of a joint acrylate—methacrylate manufacturing complex, the preferred catalyst for esterification is a sulfonic acid type ion-exchange resin. In this case the residue from the ester reactor bleed stripper can be disposed of by combustion to recover energy value as steam. [Pg.154]

Fatty JicidFster Sulfonates. Fatty acid ester sulfonates (FAES) are generally produced from methyl esters, ie, methyl ester sulfonate (MES) and prepared via sulfonation, followed by bleaching and neutralization, in a relatively difficult and complex process ... [Pg.242]

Cl Disperse Blue 87 (107) and related dyestuffs are also prepared from l-oxo-3-imino-4,7-diamino-5,6-phthaloyhsoiQdoline [13418-50-3] (111) by alkylation with corresponding alkyl haUdes (122), sulfonic esters (123), or alkyl amines (124), ie, X of RX = halogen, -toluenesulfonyloxy, or NH2. [Pg.322]

Ethers. In the presence of anhydrous agents such as ferric chloride (88), hydrogen bromide, and acid chlorides, ethers react to form esters (see Ethers). Esters can also be prepared from ethers by an oxidative process (89). With mixed sulfonic—carboxyhc anhydrides, ethers are converted to a mixture of the corresponding carboxylate and sulfonate esters (90) ... [Pg.381]

Sulfonate esters are especially useful substrates in nucleophilic substitution reactions used in synthesis. They have a high level of reactivity, and, unlike alkyl halides, they can be prepared from alcohols by reactions that do not directly involve bonds to the carbon atom imdeigoing substitution. The latter aspect is particularly important in cases in which the stereochemical and structural integrity of the reactant must be maintained. Sulfonate esters are usually prepared by reaction of an alcohol with a sulfonyl halide in the presence of pyridine ... [Pg.296]

Another deviation from the normal displacement reaction of primary tosylates occurs in nucleoside derivatives (39, 81) where cyclonucleosides and anhydronucleosides are formed by participation of a nitrogen atom (as in purine nucleosides) and oxygen atom (as in pyrimidine nucleosides ), respectively. Iodonucleosides can result from these reactions only if these cyclic compounds are prone to attack by iodide ion. Several new examples of unexpected reactions during the solvolysis of sulfonate esters in sugar derivatives have been recorded in the past few years (2, 4,5,7,15,44,62,63,94). [Pg.169]

The amount of residual sulfonate ester remaining after hydrolysis can be determined by a procedure proposed by Martinsson and Nilsson [129], similar to that used to determine total residual saponifiables in neutral oils. Neutrals, including alkanes, alkenes, secondary alcohols, and sultones, as well as the sulfonate esters in the AOS, are isolated by extraction from an aqueous alcoholic solution with petroleum ether. The sulfonate esters are separated from the sultones by chromatography on a silica gel column. Each eluent fraction is subjected to saponification and measured as active matter by MBAS determination measuring the extinction of the trichloromethane solution at 642 nra. (a) Sultones. Connor et al. [130] first reported, in 1975, a very small amount of skin sensitizer, l-unsaturated-l,3-sultone, and 2-chloroalkane-l,3-sultone in the anionic surfactant produced by the sulfation of ethoxylated fatty alcohol. These compounds can also be found in some AOS products consequently, methods of detection are essential. [Pg.444]

Although halides are common leaving groups in nucleophilic substitution for synthetic purposes, it is often more convenient to use alcohols. Since OH does not leave from ordinary alcohols, it must be converted to a group that does leave. One way is protonation, mentioned above. Another is conversion to a reactive ester, most commonly a sulfonic ester. The sulfonic ester groups tosylate, brosylate, nosylate, and mesylate are better leaving groups than... [Pg.446]

Trialkylboranes react rapidly and in high yields with a-halo ketones,a-halo esters, a-halo nitriles, and a-halo sulfonyl derivatives (sulfones, sulfonic esters, sulfonamides) in the presence of a base to give, respectively, alkylated ketones, esters, nitriles, and sulfonyl derivatives. Potassium tert-butoxide is often a suitable base, but potassium 2,6-di-tert-butylphenoxide at 0°C in THF gives better results in most cases, possibly because the large bulk of the two tert-buXy groups prevents the base from coordinating with the R3B. The trialkylboranes are prepared by treatment of 3 mol of an alkene with 1 mol of BH3 (15-16). With appropriate boranes, the R group transferred to a-halo ketones, nitriles, and esters can be vinylic, or (for a-halo ketones and esters) aryl. " °... [Pg.560]


See other pages where From sulfonate esters is mentioned: [Pg.167]    [Pg.443]    [Pg.86]    [Pg.31]    [Pg.1926]    [Pg.167]    [Pg.443]    [Pg.86]    [Pg.31]    [Pg.1926]    [Pg.87]    [Pg.168]    [Pg.169]    [Pg.177]    [Pg.200]    [Pg.119]    [Pg.202]    [Pg.442]    [Pg.399]    [Pg.495]   
See also in sourсe #XX -- [ Pg.1330 ]




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Alkyl sulfonate esters, from alcohols

Azides from sulfonate esters

Esters, sulfonate carbanions from

Esters, sulfonate from alcohols

Esters, sulfonate from aldehydes

From halo sulfonic acid esters

From sulfonates

From sulfones

Halides, alkyl from sulfonate esters

Halides, alkyl, preparation from sulfonate esters

Methyl derivatives, from sulfonate esters

Nitriles, preparation from sulfonate esters

Sulfonate ester, formation from sulfonyl

Sulfonate ester, formation from sulfonyl chloride and alcohol

Sulfonate esters

Sulfonate esters from alcohols + sulfonyl chlorides

Sulfones from esters

Sulfones from esters

Sulfonic acids from sulfonate esters

Sulfonic esters

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