Naphthalene sulfonic acid derivatives

There are three main uses for naphthalene sulfonic acid derivatives (75—79) as naphthalenic tanning material alkyl naphthalene sulfonates for industrial appHcations as nondetergent wetting agents and as dye intermediates. Consumption of naphthalene sulfonates as surfactants accounts for a large portion of usage. Naphthalene sulfonate—formaldehyde condensates are also used as concrete additives to enhance flow properties. Demand for naphthalene sulfonates in surfactants and dispersent appHcations, particularly in concrete, was expected to increase into the twenty-first century. Consumption as of 1995 was 16 x 10 kg/yr. 

The material, made by a two-step diazotization of each naphthalenic sulfonic acid derivative, is typically used in the form of the neutralized sodium salt. A similar sulfonic acid-based azo dye (4) which falls into the class of reactive dyes is also shown (76). This compound, made similarly to (3), is used as a blue dyestuff for cotton and wool. 

The pigments are synthesized by diazotizing the aniline derivative or the aniline sulfonic acid with sodium nitrite in hydrochloric acid and subsequently coupling onto the naphthalene sulfonic acid derivative, which is previously dissolved by neutralizing with a sodium hydroxide solution, producing the corresponding azo dye solution. 

Anti-HIV agents N-acyl amino-naphthalene sulfonic acid derivatives... 

Finally, a few miscellaneous compounds which were identified in the Delaware River and which have not been previously reported as water contaminants will be discussed Chloro (trifluoromethyl) aniline and chloro (trifluoromethyl) nitrobenzene (no. 55 and 56) were identified in the water, they had maximum concentrations at river mile 78. Both compounds represent common sub-structures in various pesticide and dye molecules, and several of the companies located along the river have patents using these compounds (30-32j. It is possible that these compounds are actually present in the river water as such, but it is also possible that they are formed in the GC injection port by pyrolytic degradation of larger pesticide or dye molecules (see above). All three binaphthyl-sulfone isomers (no. 92) were identified in the river water near Philadelphia. Product literature for one of the companies in the area indicates production of condensed sulfonated polymers derived from naphthalene sulfonic acid and maleic anhydride. It seems likely that the binaphthylsulfones are formed as by-products during preparation of this commercial product. 

Alkaline glucose converts the diazonium salts of l-amino-2-hydroxy-naphthalene-4-sulfonic acid and its halogen, nitro, carboxyl, or sulfonic acid derivatives into the corresponding 2-hydroxynaphthalene-4-sul-fonic acids.126 According to this patent, the yields are nearly quantitative. 

Fluorescence detectors are based on filter-fluorimeters or spectrofluori-meters. They are more selective and can be up to three orders of magnitude more sensitive than UV absorbance detectors. The detector responds selectively to naturally fluorescing solutes such as polynuclear aromatics, quinolines, steroids and alkaloids, and to fluorescing derivatives of amines, amino acids and phenols with fluorogenic reagents such as dansyl chloride (5-(dimethylamino)-l-naphthalene sulfonic acid). 

Chem. Descrip. Deriv. of naphthalene sulfonic acid Ionic Nature Anionic Uses Dispersant for all fibers Properties Powd. 

Naphthoic acid has been prepared principally by the hydrolj sis of d-naphthonitriled the overall yields from (3-naph-thylamine, from sodinm-/3-naphthalene sulfonate, and from calcium d-naphthalene sulfonate being given as (approximately) 20 per cent, 21 per cent, and 50 per cent, respectively. The acid has been prepared also by the carbonation of the Grignard reagent from the less accessible /3-bromo derivative and. more recendy, from the readily available methyl ketone. ... 

Salts of diazonium ions with certain arenesulfonate ions also have a relatively high stability in the solid state. They are also used for inhibiting the decomposition of diazonium ions in solution. The most recent experimental data (Roller and Zollinger, 1970 Kampar et al., 1977) point to the formation of molecular complexes of the diazonium ions with the arenesulfonates rather than to diazosulfonates (ArN2 —0S02Ar ) as previously thought. For a diazonium ion in acetic acid/water (4 1) solutions of naphthalene derivatives, the complex equilibrium constants are found to increase in the order naphthalene < 1-methylnaphthalene < naphthalene-1-sulfonic acid < 1-naphthylmethanesulfonic acid. The sequence reflects the combined effects of the electron donor properties of these compounds and the Coulomb attraction between the diazonium cation and the sulfonate anions (where present). Arenediazonium salt solutions are also stabilized by crown ethers (see Sec. 11.2). 

The y-nitrogen atom of a sulfonic acid azide is electrophilic and reacts in an electrophilic aromatic substitution with an activated benzene or naphthalene derivative, e.g., a phenoxide ion, forming a l-tosyl-3-aryltriazene (2.47). The 1,4-quinone diazide is obtained by hydrolysis (Scheme 2-30, Tedder and Webster, 1960). The general applicability of this reaction seems to be doubtful. With 1-naphthol the 1,2-naphthoquinone diazide was obtained, not the 1,4-isomer. 

The term coupling component referred originally to aromatic hydrocarbons, particularly benzene and naphthalene derivatives, which were required to have a hydroxy or an amino group as a substituent (sometimes, but not necessarily, accompanied by other substituents such as sulfonic acid groups). The presence of the hydroxy or amino group increases the C-nucleophilicity of the coupling component. In most cases this is a necessary requirement because the diazo components are relatively weak electrophiles. If the coupling component is phenol or a derivative of phenol ... 

Proteases are enzymes that break peptide bonds in proteins. As such they lend themselves to a variety of homogeneous assay techniques. Most employ labeling both ends of the substrate with a different tag, and looking for the appearance (disappearance) of the signal generated in the intact substrate (product). As an example, for a fluorescence quench assay, the N-terminal of a peptide is labeled with DNP and the C-terminal with MCA. As such, the peptide is fluorescently silent since the fluorescence from DNP is quenched by absorption by the MCA. Another very popular donor/acceptor pair is EDANS 5-[(2-aminoethyl)amino] naphthalene-1-sulfonic acid and DABCYL 4-(4-dimethylaminophenylazo)benzoic acid) (a sulfonyl derivative (DABSYL) [27], Upon peptide cleavage, the two products diffuse, and due to a lack of proximity, the fluorescence increases. 

The amine-reactive 5-(dimethylamino)naphthalene-l-sulfonyl (dansyl) chloride 28 [80] and related fluorophores [81, 82], as well as the 5-((2 aminoethyl)amino) naphthalene-1-sulfonic acid (EDANS) 29, are included in the naphthalene fluorophore family. Derivatives of the latter, such as compound 30, exhibit a Lm.ix/ Lem 336/520 nm, molar absorptivity (e) of 6.1 x 103 M-1 cm-1, and a fluorescent quantum yield of 0.27 in water [83], The use of EDANS is particularly interesting in FRET experiments [84, 85]. Furthermore, 4-amino-3,6-disulfonylnaphthalimides (e.g., Lucifer yellow 31), associated to a longer absorption (Lmax 428 nm) [86] are suitable polar tracers [87]. 

Naphthalenols, naphthalenediols, and their sulfonated and amino derivatives are important intermediates for dyes, agricultural chemicals, drugs, perfumes, and surfactants. The methods of manufacture include caustic fusion of naphthalene-l-sulfonic acid, hydrolysis of 1-chloro- or... 

There is surprisingly little reliable information on the sulfonation of benzo[6]thiophene or its derivatives. Benzo[6]thiophene is more readily sulfonated than naphthalene.699 Reaction with concentrated sulfuric acid at 80° gives a mixture of mono-, di-, and trisulfonic acids, reaction with 70% sulfuric acid at 80° gives a monosulfonic acid,699 and reaction with 18% oleum gives a disulfonic acid 86 in each case the orientation of the products is unknown. Treatment of benzo[6]thiophene with concentrated sulfuric acid in acetic anhydride at 20° gives 3-acetylbenzo[6]thiophene (ca. 10%) and a sulfonation product (isolated as the potassium salt), which was believed to be the 3-sulfonic acid.660 Recently, the sulfonation product has been shown to contain the 2- (8%) and 3-isomer (92%), by conversion into the sulfonyl chlorides and reduction to a separable mixture of 2- and 3-mercaptobenzo[6]thiophene.84... 

Meyer32 has shown that 2-(stilben-4-yl)- and 7-styrylbenzo[h]furans containing sulfonic acid groups can be prepared from the phenyl-iminomethyl derivatives of benzene, biphenyl, and naphthalene. 

A particularly important class of coupling components are the aminohydroxy-naphthalenesulfonic acids. Appropriate variation of the disazo component permits the development of shades ranging from orange to black. Orange and scarlet are achieved with I-acid (6-amino-l-hydroxy-naphthalene-3-sulfonic acid) and y-acid (7-amino-1-hydroxynaphthaIcne-3-sulfonic acid), whereas H-acid (8-amino-l-hydroxynaphthalene-3,6-disulfonic acid) and K-acid (8-amino-l-hydroxy-naphthalene-3,5-disulfonic acid) derivatives are useful for red to bluish-red hues. Extremely lightfast red shades are also accessible with disazo dyes ( brown dyes ). For chemical structures see Section 3.1.5). 

Consensus on nomenclature had been reached by the 1890s. Aniline was the parent of its derivatives, though sulfonic acids were considered derivatives of benzene, such as aminobenzenesulfonic acid. The prefix amino- was added to naphthalene and its derivatives. Many trivial names came into use, particularly for aminonaphthalenesulfonic acids, found in both academic and industrial research laboratories. Though IUPAC convention now numbers amino aryl compounds according to the parent hydrocarbon, the earlier system of numbering has often been retained, since some names include the positions of substituents at carbon atoms numbered according to the older systems. 

---