Naphthyl sulphonic acids

The dependence of fluorescence spectra and intensity of fluorescence of ionizable compounds on the pH of the solution enables them to he used as fluorescence indicators. The naphthyl sulphonic acids are typical examples. In the case of hydroxy and amino pyrene sulphonic acids, sharp changes in fluorescence do not occur at the same pH values as changes in absorption. This has been explained by Forster30 by considering the attainment of the ionic equilibrium appropriate to the excited state within its life time. The fluorescence of some purines and pyrimidines also depends on the acidity or alkalinity of the medium31. 

Amino Acid MJ. Benzoate 3 5-Dlnltro-benzoate Phenyl-uieldo Acid />-Toluene- sulphonate 2 4-Dicbloro-phenoxy-acetate a-Naphthyl-nreldo Acid Phthalyl Derivative... 

CHLORO-2-((2-HYDROXY-l-NAPHTHALENYL)AZO)-4-METHYLBENZENE SULFONIC ACID, BARIUM SALT (2 1) see CHP500 5-CHLORO-2-((2-HYDROXY-l-NAPHTHALENYL)AZO)-4-METHYLBENZENE SULPHONIC ACID, BARIUM SALT see CHP500 5-CHLORO-2-((2-HYDROXY-l-NAPHTHYL)AZO)-p-TOLUENE SULFONIC ACID, BARIUM SALT see CHP500... 

The following derivatives are stable towards ammonium sulphide p - acetoxymercuri-o-nitroaniline, o - acetoxy mereuri-p-broniodimethyl-aniline, 2 4-diacetoxyniereuri-a-naphthylaniine, and p-dimethylamino-phenylmercuric acetate. If the latter compound be boiled with potassium iodide solution, then treated with hydrogen sulphide, only traces of mercuric sulphide are produced. Mercury compounds from jS-naphthylamine, j8-naphthylamine-C-sulphonic acid, 1 5-naphthyl amine sulphonic acid are decomposed b ammonium suli hide, wiiilst naphthi-onic acid derivatives are only slowty attacked. 

This acid is technically known as F-acid, and is identical with the acid prepared by the diazo-reaction from Bayer s 3-naphthyl-amine-S-sulphonic acid. 

By the action of concentrated sulphuric acid on y3-naphthyl-amine two monosulphonic acids are first formed, 9-naphthylaminc-a-sulphonic acid (corresponding to the crocein acid from -naph-thol), and the yS-naphthylamine-7-sulphonic acid. 

Naphthyl blue is probably a salt of a sulphonic acid of amido-isonaphthylrosinduline, and naphthyl violet is a dyestuff of similar character. They are principally intended for silk, on which they show a red fluorescence. 

Aerial oxidation of this affords anthraquinone in 37% yield. Both 1-naphthyl and 2,4-dimethylbenzene sulphonates follow the same path but yield only traces of the corresponding quinone. In the last case, 2,4-dimethylbenzenesulphonate, the quinone is accompanied by 0.8% of 2,4-dimethylphenol. The second path involves loss of sulphur trioxide to yield aryl radicals which afford the products, the arene and/or the biaryl, shown in Scheme 17212,213. Other studies have shown that anthraquinone-1-sulphonic acid (256)214,215 and anthraquinone-2-sulphonate216 are also photochemically labile. A study of the photochemical reactivity of azulene sulphonic acids has also been reported217. Photochromism has been studied with respect to the stilbene derivative 257218. 

Cryst. M.p. 249° (243°). Sol. hot CS., CHCI3. Spar. sol. CgHj. Insol. H O. HgSOg —>HgSOj -f naphthalene-1-sulphonic acid. CHa COOH — mercuri-l-naphthyl acetate -f naphthalene. HgClg—y merouri-1-naphthyl chloride. 

EBT indicator solution Dissolve 0.2g EBT (3-hydroxy-4-[(l-hydroxy-2-naphthyl)azo]-7-nitro-l-naphthalene-sulphonic acid, sodium salt) in 100 mL methanol. Filter the solution and store between 0 and 5 C. 

The batch in the measuring kettle consists of an aqueous solution of naphthyl-amine sulphonic acid B or pure water. 

Di-(l-naphthylmethyl)sulphone forms an excimer but does not react to give an intramolecular cycloaddition product like the corresponding ether but rather fragments to give sulphur dioxide and (l-naphthyl)methyl radicals (Amiri and Mellor, 1978). I-Naphthylacetyl chloride has a very low quantum yield of fluorescence and this is possibly due to exciplex formation between the acyl group and the naphthalene nucleus (Tamaki, 1979). Irradiation leads to decarbonylation. It is known that acyl chlorides quench the fluorescence of aromatic hydrocarbons and that this process leads to acylation of the aromatic hydrocarbon (Tamaki, 1978a). The decarboxylation of anhydrides of phenylacetic acids [171] has been interpreted as shown in (53), involving... 

The amido-sulphonic adds, since they are derivatives of a primary amine, may like them be diazotised by tile action of nitrous add upon tins fact depends their great technical importance. If the diazo-com-pounds thus obtained are combined with amines or phenols, azo dyes are formed which contain the sulphonic add group, and in the form of their alkali salts are soluble in water. Sulplianilic acid particularly, and its isomer, metanilic add, obtained by the reduction of m-nitro-benzenesulphonic add, as well as the numerous mono- and poly-sul-phonic acids derived from a and / naphthyl amines, find extensive technical application in the manufacture of azo dyes-... 

Intermolecular acid catalysis using a series of mainly carboxylic acids involves reaction of N-protonated naphthyl sulphamate with carboxylate anions in the rate-determining step. The / nuc value for attack (0.33) is similar to that reported by the same group for the reaction of phenolate ions with tertiary amine sulphonate (0.23). Stereoelectronic effects are suggested as governing the type of mechanism operating in these systems. 

Victor Merz (Odessa, 12 December 1839-Ziirich, 25 May 1904) was associate professor (1869) and professor (1871) in the university of Zurich. He worked first on inorganic chemistry. He synthesised ketones from acid chlorides and hydrocarbons, sodium formate from carbon monoxide, and oxalic acid by heating alkali formates. He prepared aromatic carboxylic acids by distilling sulphonates with potassium cyanide and hydrolysing the nitriles produced, discovered a- and j8-naphthoic acids, and prepared j8-naphthyl-amine from j8-naphthol by the action of ammonia and zinc chloride. ... 

Aryloxy- 3,5-Dinitro- 1-Naphthyl p-Toluene- Bromo-Benzoate acetic acid benzoate carbamate sulphonate derivative... 

No evidence could be obtained for the formation of 2ff-benzo[i>]thiet or its valence tautomer by irradiation of 3/f-l, 2-benzodithiole l,l-dioxide. Naphtho-[l,8-6c]thiet (58) has been prepared and its 5-oxide, and S -dioxide, have been obtained by oxidation with m-chloroperoxybenzoic acid. All three compounds react with lithium aluminium hydride to give ring-opened products as the result of hydride attack on sulphur. After reduction and methylation, (58) gave the methyl sulphide (59), and the 5-oxide gave bis(a-naphthyl) disulphide (75%) together with (58) (6%) and the corresponding sulphone (4%), which was the major product (85%) from the 55-dioxide (Scheme 8). Thiets are believed to be... 

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