2,6-hydroxynaphthoic acid

Hydroxy-2-naphthoic acid. (See also Beta-hydroxynaphthoic acid). 

Polymers based on these structures became available as Victrex SRP (ICI), Vectra (Hoechst) and Xydar (Amoco). It is reported that the Vectra materials are based on p-hydroxybenzoic acid and hydroxynaphthoic acid monomers, whilst Xydar is based on terephthalic acid, p-hydroxybenzoic acid and pp -dihydrox-ybiphenyl. Whilst properties vary between grades, in general they possess the following outstanding properties ... 

Seiler and Wirz have reported a study of the photohydrolysis of eight isomeric trifluoromethylnaphthols.<144) Six of the eight isomers studied underwent hydrolysis cleanly to produce quantitative yields of the corresponding hydroxynaphthoic acids ... 

Naphthol AS is the condensation product of p-hydroxynaphthoic acid and aniline Naphtol AS is the trade name of this product sold by Hoechst AG, Germany. Pigments that are known as Naphtol AS compounds in Germany are referred to in the USA as Naphthol Reds. 

Using amine, 2-hydroxynaphthoic acid, and aromatic diamine as starting materials, there are two pathways I and II that lead to the desired products ... 

Compared with other polymeric materials. LCPs have very high unidirectional properties. Iei/nt7 1 (Celanese Corp.t resins are primarily aromatic polyesters based on p-hydroxybenzoic acid and hydroxynaphthoic acid monomers. Xytlar " (Celanese Carp.) injection molding resins are polyesters based on terephthalic acid. />. p -dihydruxybiphenyl and p-hydroxybenzoic acid Differences in monomers are primarily responsible for the differences in specific properties and end uses. The fibrous nature of the polymers imparls good impact strengths. 

The BON or BONA Reds and Maroons derive their name from /(-hydroxynaphthoic acid, also known as 3-hydroxy-2-naphthoic acid. BON is used as a general coupling component for the entire group with various dia/oi.i/ed airlines containing salt-forming groups. 

The coordination chemistry of hydroxynaphthoic acids and related ligands has been studied mainly with the aim of obtaining stability constants for the complexes formed. There is not, therefore, much work on the stereochemistry and coordination modes of these ligands. 

The dehydration of peri-hydroxynaphthoic acids, which can be obtained from peri-bromo- or peri-aminonaphthoic acids, gives rise to naphtho-... 

Diazo Components With Amino alkyl Groups. Yellow dyes are prepared by ami-nomethylation of 2-(4 -aminophenyl)-5-methylbenzothiazole followed by diazoti-zation and coupling with acetoacetarylides. Red cationic dyes are obtained with naphthols or hydroxynaphthoic acid arylides. All are suitable for dyeing paper. The bleachability of these dyes is important for the recycling of waste paper [84], The aminomethylation of aromatic amines is carried out by reaction with formal-... 

Reaction of chlorosulfonic acid with mono- [141] or disazo dyes [142] yields sulfonyl chlorides, which can then be transformed into cationically substituted sulfonamides by reaction with dialkylaminoalkylamines. The coupling product of diazotized 2-anisidine with 2-hydroxynaphthoic acid arylide upon such treatment dyes paper red, and the azo dye from tetrazotized dianisidine and l-phenyl-3-methyl-5 -pyrazolone gives yellowish orange shades. 

PES fibers are almost exclusively colored with disperse dyes. For some time, dia-zotization dyes were used for dark shades. They are coupled in the fiber with suitable components (e.g., 2-hydroxynaphthoic acid). Although fast colors are obtained, the dyeing process is time-consuming and susceptible to failure, and dyeing reproducibility is poor. Vat dyes are also occasionally used for PES dyeing. Small molecular thioindigo derivatives, in particular, diffuse into PES fibers if they are applied in the thermosol process. 

Not surprisingly, similar behaviour occurs in o-hydroxynaphthoic acids. Hirota (1962) interpreted his results on 3-hydroxy-2-naphthoic acid in terms of the rapid attainment of equilibrium between the... 

Poly(p-phenylene terephthalamide (Kevlar) (b) copolyester of p-hydroxybenzoic acid and biphenylene terephthalate (Xydar) (c) copolyester of p-hydroxybenzoic acid and 2,6-hydroxynaphthoic acid (Vectra). 

In the case of jS-hydroxynaphthoic acid the mercury enters position 1, and may be removed again by the action of iodine in potassium iodide solution. 

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