Halogenated sulfones

In general, the presence of fatty acid groups in the phosphoHpid molecule permits reactions such as saponification, hydrolysis, hydrogenation, halogenation, sulfonation, phosphorylation, elaidinization, and ozonization (6). 

Anthraquinone can be sulfonated, nitrated, or halogenated. Sulfonation is of the greatest technical importance because the sulfonic acid group can be readily replaced by an amino or chloro group. Sulfonation with 20—25% oleum at a temperature of 130—135°C produces predominandy anthraquinone-2-sulfonic acid [84-48-0]. By the use of a stronger oleum, disulfonic acids are produced. The second sulfonic acid substituent never enters the same ring a mixture of 2,6- and 2,7-disulfonic acids is formed (Wayne-Armstrong rule). In order to sulfonate in the 1-, 1,5-, or 1,8-positions, mercury or one of its salts must be used as a catalyst. 

In these compounds the following substituents can be present alkyl,alkenyl,aryl, halogen,sulfonic acid, amino, hydroxyalkyl, acyl, and carboxyl. The cleavages of 5,5 - (109) and 3,5 -diisoxazolyl (111) proceed similarly both isoxazole rings are cleaved in the former (109—> 110). ... 

The reaction takes place above 20 atms press and above 482°, with suitable H2 partial press and contact time necessary to obtain destructive hydrogenation without the formation of poly merized material. The resulting hydroformed naphthas may be halogenated, sulfonated or nitrated... 

Equipped with these reference trends for steric and electronic effects, one is prepared to survey more general classes of electrophilic aromatic substitution on benzocycloalkenes. Such reactions include nitration, halogenation, sulfonation, and alkylation. Each has its own mechanistic peculiarities, but their product distributions can be rationalized by consideration of the appropriate reference. 

In this section we use benzene as a typical aromatic compound to study three basic reactions halogenation, sulfonation, and nitration. In the case of halogenations, the electrophile is the X ion (X = Cl or Br). In sulfonation and nitration, the electrophiles are SO3 and NO2, respectively. In each case, part of the mechanism involves the generation of the electrophile. 

In nitration, halogenation, sulfonation, and acylation, the reactions are easy to control with temperature. The processes deactivate the ring toward further substitution, so the reactions inhibit further reaction. 

In addition to oxidation and reduction reactions, naphthalene readily undergoes substitution reactions such as nitration, halogenation, sulfonation, and acylation to produce a variety of other substances, which are used in the manufacture of dyes, insecticides, organic solvents, and synthetic resins. The principal use of naphthalene is for the production of phthalic anhydride, CgbLO,. 

In a similar route, Takahashi et al. made use of non-halogenated sulfones [37]. 

Cesium fluoride has been used to displace halogens, sulfonate groups and nitro groups among others, with fluorine. 1-Bromooctane (1), ethyl bromoacetate (2), benzyl bromide (3) and octyl tosylate (4) have been converted to the respective fluorides 5-7 by treatment with cesium fluoride in the presence of 10% tetraalkylammonium salt (Bu4NBr or Aliquat 336) in the absence of solvent.166... 

Table 11. Replacement of Halogen, Sulfonate Esters and Nitro Groups in Organic Substrates by TBAF...

Acenaphthene. (CAS 83-32-9]. Acenaphthene is a hydrocarbon, C12H10, present in high temperature coal tar. Acenaphthene may be halogenated. sulfonated. and nitrated in a manner similar to naphthalene. Oxidation first yields acenaphthenequmone, followed by 1.8-naphthalenedicarboxyhc acid anhydride and pesticides. 

Cmde lecithin contains a number of functional groups that can be successfully hydrolyzed, hydrogenated, hydroxylated, ethoxylated, halogenated, sulfonated, acylated, succinylated, ozonized, and phosphorylated, to name just a few possibilities (1). The only chemically modified food-grade products produced in significant commercial quantities at the present time are the ones obtained by hydroxylation, acetylation, and enzymatic hydrolysis (58). Hydroxylated or acylated lecithins represent chemical modifications to improve the functionality in water-based systems. 

Like other aromatic compounds, these five-membered heterocycles undergJ nitration, halogenation, sulfonation, and Friedel-Crafts acylation. They are mucji more reactive than benzene, and resemble the most reactive benzene derivatives (amines and phenols) in undergoing such reactions as the Reimer-Tiemann reaction, nitrosation, and coupling with diazonium salts. 

Azides from Halogen, Sulfonate and Sulfate Derivatives 245... 

Aryl amine intermediates for azo and triphenylmethane dyes, as well as a number of vat dye (anthraquinone) intermediates, are made from compounds such as benzene, alkyl benzenes (toluene and higher homologues), phenol and naphthalene. A limited number of reactions are used to produce the most important dye intermediates, including nitration, reduction, halogenation, sulfonation, /V-alkylation, /V-acylation and alkali fusion33,34. 

A method122 for hydrolyzing benzylidene and isopropylidene acetals by means of 90% trifluoroacetic acid is recommended. The procedure is mild and rapid, and does not affect esters, halogens, sulfonates, or azides. 

The effect of substituents including halogen, sulfonate, and nitro will be discussed in more detail in Sections 6.5.1, 6.8.1, and 6.8.2, but a few general comments may usefully be inserted here. The presence of these electron-attracting substituents generally increases resistance to bacterial degradation, although at least for naphthalenes, the substituted compounds can be... 

---