Phenols from sulfonic acids

Photosynthesis of azo-dyestuffs has been reported to be effected by the irradiation of o-quinone diazides. The reaction proceeds via the contraction of the diazide CCXV to the cyclic ketene CCXVI which adds water to form the eyclopentadiene carboxylic acid CCXYII. The latter couples with unchanged CCXV (obtained from 2-amino-l-phenol-4-sulfonic acid) to form the azo-dyestuff CCXVTII.270 Similarly, V-heterocyclic azo-dyestuffs, e.g., CCXX is obtained by the photolysis of CCXIX.275... 

Diazo 2-bromo-6-chloro-p benzoquinone [ called 6-Chlor-2-brom-p-chinon-diazid-(4) or 6-Chlor-2 -brom-4-diazo-phenol in Ger], yel-red ndls (from hot eth, benz or chlf), explodes violently on heating to 15 0° v sol in hot ale si sol in hot eth or chlf insol in w was obtd by addn of bromine water to an aq soln of 4-diaZo-6-chloro -phenol-2 sulfonic acid(Refs 2 3)... 

Remarkably, enhanced binding by the chelate effect is occasionally seen not in free energies of complexation the association constants of e.g. amino acids with sulfonatocalix[4]arenes are quite close the ones observed with phenol-4-sulfonic acid as single host unit Only AH shows an advantage of the macrocycle with AH = 30 compared to 1 kJ/mol, compensated by a much smaller entropy disadvantage with the smaller monomeric host, which changes from e.g. TAS = -12 kJ/mol to favorable +12 kJ/mol.[34]... 

Partial condensers, 24, 341 Partial reduction, 79, 113 Patent blues, 301 Permanent red 2G, 267 Phenanthrene, 1 Phenol, 51, 86 from chlorobenzene, 76, 88 technical observations, Phenolphthalein paper, 395 Phenols, separation, 30 Phend-o-svdfonic acid, 51 Phenol-m-sulfonic acid, 144,145... 

The reaction of di- and polysulfonic acids can usually be carried out so that the replacement of the sulfo groups by hydroxyls takes place stepwise (partial alkali fusion). Thus, phenol-m-sulfonic acid is obtained from benzene-m-disulfonic acid under mild conditions, while resorcinol is formed under more vigorous conditions (see page 144) similarly, naphthalene-l,5-disulfonie acid yields, first, l-naphthol-5-sulfonic acid, then l,5 dihydroxynaphthalene, both valuable azo dye... 

Nitroso compounds are formed as intermediates in this reaction. Yields from sulfonic acids, carboxylic acids, and nitro compounds, amongst others, are poor,424 but those from tertiary amines and phenols are often very good,423,426 although naphthols give only the nitroso derivatives for example, yields are 70% from A,iV-diethylaniline,423 96% from phenol,426 98% from o- or 7W-cresol,426 95% from chlorophenol,426 and 75-85% from o-hydroxybenzene-sulfonic acid 428 the diazonium group enters para to the NR2 or OH group. 

Aryl arenesulfonates mostly crystallize readily and are useful for identification of phenols or sulfonic acids they are easily obtained from the acid chlorides and phenols in the presence of alkali689 or a tertiary base690 by the Schotten-Baumann procedure. 

Benzene SuIfona.tion. In the benzene sulfonation process, benzene reacts with concentrated sulfuric acid to form benzenesulfonic acid at about 150°C. The benzenesulfonic acid is neutralized with sodium sulfate to produce sodium benzenesulfonate, which is then fused with caustic soda to yield sodium phenate. The sodium phenate is acidified with sulfur dioxide and a small amount of sulfuric acid to release the phenol from the sodium salt. The phenol yield by this process can be as high as 88 mol % to that of the theoretical value based on benzene. Plants employing this technology have been shut down for environmental and economic reasons. 

Toluenesulfonic Acid. Toluene reacts readily with fuming sulfuric acid to yield toluene—sulfonic acid. By proper control of conditions, /)i7n7-toluenesulfonic acid is obtained. The primary use is for conversion, by fusion with NaOH, to i ra-cresol. The resulting high purity i7n -cresol is then alkylated with isobutylene to produce 2 (i-dii-tert-huty -para-cmso (BHT), which is used as an antioxidant in foods, gasoline, and mbber. Mixed cresols can be obtained by alkylation of phenol and by isolation from certain petroleum and coal-tar process streams. 

ButylatedPhenols and Cresols. Butylated phenols and cresols, used primarily as oxidation inhibitors and chain terrninators, are manufactured by direct alkylation of the phenol using a wide variety of conditions and acid catalysts, including sulfuric acid, -toluenesulfonic acid, and sulfonic acid ion-exchange resins (110,111). By use of a small amount of catalyst and short residence times, the first-formed, ortho-alkylated products can be made to predominate. Eor the preparation of the 2,6-substituted products, aluminum phenoxides generated in situ from the phenol being alkylated are used as catalyst. Reaction conditions are controlled to minimise formation of the thermodynamically favored 4-substituted products (see Alkylphenols). The most commonly used is -/ fZ-butylphenol [98-54-4] for manufacture of phenoHc resins. The tert-huty group leaves only two rather than three active sites for condensation with formaldehyde and thus modifies the characteristics of the resin. 

Potassium phenol-4-sulfonate (4-hydroxybenzene-l-sulfonic acid K salt) [30145-40-5] M 212.3. Crystd several times from distilled water at 90°, after treatment with charcoal, by cooling to ca 10°. Dried at 90-100°. 

For many years phenol was made on a large industrial scale from the substitution reaction of benzene sulfonic acid with sodium hydroxide. This produced sodium sulfite as a by-product. Production and disposal of this material, contaminated with aromatic compounds, on a large scale contributed to the poor economics of the process, which has now been replaced by the much more atom economic cumene route (see Chapter 2, Schemes 2.2 and 2.3). 

Organophilic polyphenolic materials for oil-based drilling fluids have been described [407], The additives are prepared from a polyphenolic material and one or more phosphatides. The phosphatides are phosphoglycerides obtained from vegetable oils, preferably commercial lecithin. Humic acids, ligno-sulfonic acid, lignins, phenolic condensates, tannins the oxidized, sulfonated, or sulfomethylated derivatives of these polyphenolic materials may serve as polyphenolic materials. 

Apart from complex formation involving metal ions (as discussed in Chapter 4), crown ethers have been shown to associate with a variety of both charged and uncharged guest molecules. Typical guests include ammonium salts, the guanidinium ion, diazonium salts, water, alcohols, amines, molecular halogens, substituted hydrazines, p-toluene sulfonic acid, phenols, thiols and nitriles. 

Ligand-free catalysts have been prepared from the following types of nickel(II) compounds nickel salts of long-chain aliphatic or aromatic carboxylic acids (10, 11) or of sulfonic acids (11), nickel enolates of /3-diketones (11) [e.g., nickel acetylacetonate (4, 12)] or their imino derivatives (11, 13), nickel phenolates (11), dithiocarbamates (14), and mer-captides (15). 

This group has examples of many types of acids derived from aliphatic, aromatic and heterocyclic radicals, with carboxylic, phenolic or sulfonic or related functional substituents. Individually indexed acids are ... 

There are a number of limitations on the Brpnsted relationship. First of aU, the relation holds only for similar types of acids (or bases). For example, carboxylic acids may have a different a values compared to sulfonic acids or phenols. Because charge, and likewise solvation, can greatly influence the reaction rate, deviations of net charge from one catalyst to another can also influence Brpnsted plots. Another limitation on this relationship relates to temperature. Reaction rates and the corresponding dissociation constants for the acids must all be measured at the same temperature (and, most rigorously, in the same solvent). For some systems, this may prove infeasible. A third limitation is that the reaction must indeed be subject to general acid (or base) catalysis. For certain catalysts, deviations from a linear relationship may indicate other modes of action beyond general acid/... 

Phenol was prepared before World War I through the distillation of coal tar. The first synthetic process involved the sulfonation of benzene followed by desulfonation with a base. In this process, benzene sulfonic acid is prepared from the reaction of benzene and sulfuric acid ... 

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