Hydroxynaphthalene, substituted

Successful decarboxylations where the substituents favor classic electrophilic aromatic substitution are known. Reaction of 2-hydroxy-l-naphthalenecarboxylic acid with mercuric acetate in cold acetic acid has been reported to give 2-hydroxynaphthalen-l-ylmercuric acetate [Eq. (71)] (84). Although the result probably requires reinvestigation,... 

Diazotization of 3-(4-aminophenyl)sydnones followed by reaction with 1- or 2-hydroxynaphthalene provides azo dyestuff materials <1998MI209>. A new type of reaction between 4-acetyl-3-arylsydnones and hydrazine yields substituted pyrrolidinones by a cycloaddition process involving loss of nitric oxide (Equation 20) <1999H(51)95, 2001AHC73>. 

Biehl and coworkers170 have described a facile one-step preparation of substituted 3-benzyl-l-hydroxynaphthalene-2-carbonitriles 301 and 11 -amino-5//-an thra[2,3-... 

The one-bond 7( C, H) coupling constant in mono-substituted benzenes does not correlate with the electronegativity, but can be correlated to a combination of Hammett parameters . The lack of strict correlations can also be seen from 2-hydroxynaphthalene in which 7( C-1, H-1) is decreased slightly compared to naphthalene, whereas 7( C-3, H-3) is increased slightly . For 1-hydroxynaphthalene, an increase is seen for the C-8,H-8 coupling constant of the peri bond . For a general introduction see elsewhere . ... 

Chloro-l-hydroxynaphthalene is converted into the sulphonate 246 on eosin-sensitized irradiation in the presence of sodium sulphite. A study of the chain substitution of the chloro group in 4-chloro-l-hydroxynaphthalene by aqueous sodium sulphite has shown that two mechanisms for the photoinitiation have been identified and two intermediates have been detected a radical anion of 4-chloro-l-naphthoxide and the sulphite radical anion. Thus, an SjjajI mechanism is suggested and is one that involves reaction with the radical anion of sulphite. An example of the S n 1 process between a phenol and the (2-cyanoaryl)azo-f-butylsulphides has been reported. The 1 reactivity of several compounds (Scheme 27) have demonstrated that 247 is a product however, this is also photochemically reactive and is converted into the cyclic ether 248 . 

In conclusion, we have discovered that chelation with alkaline metal ion, especially Li+, enhances markedly chemiluminescence efficiency of CTICL for an even pattern hydroxyaryl-substituted dioxetane, i.e., bicyclic dioxetane bearing a 3-hydroxynaphthalene-2-yl group 1 in THF. 

A dye component that is used frequently is H acid (l-amino-8-hydroxynaphthalene-3,6-disulfonic acid). Production of this comparatively complex substitution pattern requires a series of different chemical reactions. The known side reactions and subsequent reactions on sulfonation and nitration of the naphthalene system and high-pressure hydrolysis of its substituents reduce the yield of the target product. If, as a consequence, intermediate isolations are unavoidable during the course of the process to prevent a gradual increase in the amount of by-products, additional product losses in mother and wash liquors will occur. Management of the often considerable quantities of solid waste and wastewater is therefore an important consideration in the production of H acid. 

When hydroquinone as hydroxy compound is substituted by 2,7-di-hydroxynaphthalene, the glass transition temperature increases, while the melting temperature and the thermal stability decrease with the increase of the 2,7-naphthalene moieties. ... 

Azo coupling of diazotized orthanilic acid with the sodium salt of IV-acetyl J acid (7-acetylamine-4-hydroxynaphthalene-2-sulfonic acid) (22) yields mainly coupling ortho to the hydroxy group. Substitution at both activated positions is significantly ster-ically hindered but ionization of the hydroxy group of (22) at higher pH causes additional electrostatic interaction on formation of the a-complex for substitution at the favoured position decreasing the rate of reaction. 

In their report, Khurana and his group [81] also showed that DBU (10mol%) can effectively catalyze the three-component cyclocondensation reaction between aromatic aldehydes, malononitrile or ethyl 2-cyanoacetate, and 2-hydroxynaphthalene-l,4-dione in aqueous medium under reflux to afford 2-amino-4H-benzo[ ] chromenes (10). A series of diversely substituted 2-amino-4-aryl-5,10-dioxo-5,10-dihydro-4ff-benzo[g]chromene-3-carbonitriles and ethyl-2-amino-4-aryl-5,10-dioxo-5,10-dihydro-4H-benzo[j]chromene-3-carboxylates were synthesized using this protocol in excellent yields (Scheme 5). The reactions were claimed to be remarkably clean, and no chromatographic purification was required. 

Irradiation of 4-chloro-l-hydroxynaphthalene in aqueous solution of sodium sulfite caused the substitution of the chlorine atom by sulfite. The mechanism was rationalized as involving the sulfite radical anion in a chain S l process [207]. The reaction led to sulfonic acids in the photolysis of various para substituted anilines a halogen or a SOjX (X = CHj, NH, CFj) group was replaced, thus leading to the corresponding sulfonic acid [208]. As for the p-sulfonyl precursors, experiments with labelled sulfite confirmed that the formation of the products involved cleavage of the aryl-S bond. 

Ivanov, V.L., Lyashkevich, S.Y., and Lemmetyinen, H., The mechanism of photochemical chain substitution of chlorine by sulpho group in 4-chloro-l-hydroxynaphthalene,/. Photochem. Photobiol. A Chem., 109, 21, 1997. 

Figure IX-L-19. Absorption cross sections for a series of HO-substituted aromatic hydrocarbons, phenol, 2-hydroxynaphthalene, and 3-hydroxyphenanthrene as measured in nonpolar solvents (data from Lang, 1961-1971). Actinic flux is given by the heavy gray curve as a function of wavelength in the lower troposphere for an overhead Sun.

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