Sulfonate group reactive aromatic

We will discuss it here for the model case of azo coupling of 2-amino-7-naphthol (the presence or absence of sulfonic groups is not relevant for the mechanistic problem of orientation). The experimental results with specific aminonaphtholsulfonic acids in this Section can be discussed on the basis of the folloiving paragraphs, equation (70) and Figure 3 written for 2-amino-7-naphthol. 2-Amino-7-naphthol (757) can be substituted at the 1- or the 8-position. The substitution at the 1-position is determined only by the amino ammonium equilibriiun. As discussed in Section 4.1, an aromatic amine is reactive in azo coupling reactions only in its basic equilibrium form, e.g. for 2-amino-7-naphthol in form 757, but not in form 150. 

A reactive aromatic sulfonyl fluoride monomer, iV-(fluorosulfonyl)phenyl acrylamide, was prepared by Hart and Timmerman and its copolymerization with other monomers was reported63. However, their use as intermediates for the derivation of various sulfonyl-or sulfone-group-containing polymers is widely practiced. Thus, the —S02C1 group in a material trade-named Hypalon (DuPont) is used as a handle for the subsequent vulcanization of this elastomer. 

The original preparation of aromatic polysulfones was described in 1958. This was followed by investigations of many different structures of polysulfones. One current commercial material is a condensation product of 2,2 -bis(hydroxyphenyl) propane with 4,4 -bis(chlorophenyl) sulfone. It fohns by a ) llliamson synthesis, because the reactivity of the halogens is enhanced by the sulfone groups ... 

Recently, Kobayashi noticed that the presence of a small amount of a surfactant such as sodium dodecyl sulfate (SDS) showed a remarkable enhancement of the reactivity in the Mukaiyama-catalyzed aldol reaction in pure water using Yb(OTf)3 or better Sc(OTf )3 as the catalyst without addition of the surfactant, the reaction was very sluggish (Scheme 8.4). Other surfactants such as calix[6]arene derivatives bearing sulfonate and alkyl groups or aromatic and aliphatic anionic surfactants have also been found to be highly effective in the aqueous Mukaiyama aldol reactions in pure water, affording the aldol products in high yields. This was probably due to the formation of micelles which stabilized the labile silyl enol ethers and thus promoted the aldol reaction. 

Chlorosulfonyl styrene-divinylbenzene copolymer is a highly reactive intermediate used in organic synthesis. The aromatic styrene groups of the copolymer are sulfonated with chlorosulfonic acid in dichloroethane, followed by chlorination of the sulfonate groups with phosphorus pentachloride-phosphorus oxychloride mixture. ... 

Dyes, Dye Intermediates, and Naphthalene. Several thousand different synthetic dyes are known, having a total worldwide consumption of 298 million kg/yr (see Dyes AND dye intermediates). Many dyes contain some form of sulfonate as —SO H, —SO Na, or —SO2NH2. Acid dyes, solvent dyes, basic dyes, disperse dyes, fiber-reactive dyes, and vat dyes can have one or more sulfonic acid groups incorporated into their molecular stmcture. The raw materials used for the manufacture of dyes are mainly aromatic hydrocarbons (67—74) and include ben2ene, toluene, naphthalene, anthracene, pyrene, phenol (qv), pyridine, and carba2ole. Anthraquinone sulfonic acid is an important dye intermediate and is prepared by sulfonation of anthraquinone using sulfur trioxide and sulfuric acid. 

Reactions other than those of the nucleophilic reactivity of alkyl sulfates iavolve reactions with hydrocarbons, thermal degradation, sulfonation, halogenation of the alkyl groups, and reduction of the sulfate groups. Aromatic hydrocarbons, eg, benzene and naphthalene, react with alkyl sulfates when cataly2ed by aluminum chloride to give Fhedel-Crafts-type alkylation product mixtures (59). Isobutane is readily alkylated by a dipropyl sulfate mixture from the reaction of propylene ia propane with sulfuric acid (60). 

The hydroxyl group is a strongly activating, ortho- and para-directing substituent in electrophilic aromatic substitution reactions (Section 16.4). As a result, phenols are highly reactive substrates for electrophilic halogenation, nitration, sulfonation, and lTiedel-Crafts reactions. 

---