Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Of 2-naphthol

Naphthol is mainly used in the manufacture of the insecticide carbaryl (59), l-naphthyl A/-methyicarbamate/ iJ-2j5 - (Sevin) (22), which is produced by the reaction of 1-naphthol with methyl isocyanate. Methyl isocyanate is usually prepared by treating methylamine with phosgene. Methyl isocyanate is a very toxic Hquid, boiling at 38°C, and should not be stored for long periods of time (Bhopal accident, India). India has developed a process for the preparation of aryl esters of A/-alkyl carbamic acids. Thus l-naphthyl methylcarbamate is prepared by refluxing 1-naphthol with ethyl methylcarbamate and POCl in toluene (60). In 1992, carbaryl production totaled > 11.4 x 10 t(35). Rhc ne-Poulenc, at its Institute, W. Va., facihty is the only carbaryl producer in United States. [Pg.497]

Technologically, the most important examples of such couplers are 1-naphthylamine, 1-naphthol, and sulfonic acid derivatives of 1-naphthol (Fig. 2). Of great importance in the dyestuff industry are derivatives of l-naphthol-3-sulfonic acid, such as H-acid (8-amino-l-naphthol-3,6-disulfonic acid [90-20-0])... [Pg.428]

Tezuka s group (Tezuka and Ando, 1985 Tezuka et al., 1986) was able to isolate and characterize the benzenediazo ether of 1-naphthol (6.10). They stirred a solid mixture of the molecular complex 6.9 formed between an a-azohydroperoxide acid and benzene with an excess of 1-naphthol at room temperature in the dark for several hours. The separation of this solid by thin layer chromatography (silica gel, with a benzene-ethyl acetate mixture [9 1] as eluent) afforded the diazo ether 6.10 as a yellow oil in 17 % yield, together with 4- and 2-phenylazo-l-naphthol (6.11 and 6.12, 4% and 42%, respectively), 4-phenylbenzaldehyde (32%), benzoic acid (23%), and traces of other compounds (Scheme 6-6). Higher yields of the diazo ether (up... [Pg.114]

Quantitative studies based on kinetic measurements using strongly electrophilic diazonium ions and, as coupling components, 1-naphthol, 2-naphthol-6-sulfonic acid, and resorcinol in aqueous acid were made by Sterba and coworkers (Kropacova et al., 1970 Kavalek et al., 1970 Sterba and Valter, 1972 Machackova et al., 1972a). In a typical case (2,6-dichloro-4-nitrobenzenediazonium ion and 1-naphthol) the dependence of the logarithm of the measured rate constant (ks) on pH was linear with a slope of 1. At pH < 1, however, a practically constant value of ks was obtained. The measured rate constants therefore correspond to Scheme 12-62, in which the first term relates to the reaction of the naphthoxide ion and the second to that of the undissociated naphthol Ka is the acidity constant of 1-naphthol. [Pg.348]

Table 12-2. Rate constants (m-1 s-1) for azo coupling reactions of 1-naphthol and resorcinol, the corresponding anions, and some jnethoxy derivatives in water at 20 °C. Data from Kropacova et al., 1970 Kavalek et al., 1970 Sterba and Valter, 1972 Machackova et al., 1972a. Table 12-2. Rate constants (m-1 s-1) for azo coupling reactions of 1-naphthol and resorcinol, the corresponding anions, and some jnethoxy derivatives in water at 20 °C. Data from Kropacova et al., 1970 Kavalek et al., 1970 Sterba and Valter, 1972 Machackova et al., 1972a.
Table 12-4. Inductive effect and steric hindrance in the intermediate of azo coupling of 1-naphthol-3-sulfonic acid in the 2- and 4-positions, respectively (Stamm and Zollinger, 1957). Table 12-4. Inductive effect and steric hindrance in the intermediate of azo coupling of 1-naphthol-3-sulfonic acid in the 2- and 4-positions, respectively (Stamm and Zollinger, 1957).
More than 100 years ago Noelting and Grandmougin (1891) reported that in the azo coupling reaction of equimolar amounts of 1-naphthol and 4-chlorobenzenediazo-nium ion in water, an appreciable amount of the 2,4-bisazo compound is obtained besides the expected 2- and 4-monoarylazo-l-naphthols. The percentage of the 2,4-bisazo compound is particularly high under alkaline conditions (up to 20%). [Pg.372]

Kinetic isotope effects have not been observed in the reaction of 1-naphthol-4-sulphonic-2-acid with 2-methoxydiazobenzene127, imidazole-2,4,5-d3 with 4-diazobenzene sulphonic acid128, or indole-3- / with 4-nitrodiazobenzene12S, nor has base catalysis been observed in those cases where it has been measured in each of these reactions one or both of the reagents is relatively reactive. [Pg.53]

Bollag J-M, EJ Czaplicki, RD Minard (1975) Bacterial metabolism of 1-naphthol. J Agric Food Chem 23 85-90. [Pg.417]

Larkin Ml (1988) The specificity of 1-naphthol oxygenases from three bacterial isolates, Pseudomonas spp. (NCIB 12042 and 12043) and Rhodococcus sp. (NCIB 12038) isolated from garden soil. EEMS Microbiol Lett 52 173-176. [Pg.421]

Samanta SK, AK Chakraborti, RK Jain (1999) Degradation of phenanthrene by different bacteria evidence for novel transformation sequences involving the formation of 1-naphthol. Appl Microbiol Biotechnol 53 98-107. [Pg.422]

On integration of the above system of differential equations until B has been completely consumed U, W, and Z values are obtained. Monoazo dyes concentrations are then calculated using Ekjns. (5.4-175) and (5.4-176). The concentration of 1-naphthol is calculated knowing its surplus for the reaction and the concentration of bisazo dye S can be determined from any of the mass balances ... [Pg.343]

Lukeman, M. Veale, D. Wan, R Munasinghe, V. R. N. Corrie, J. E. T. Photogeneration of 1,5-naphthoquinone methides via excited-state (formal) intramolecular proton transfer (ESIPT) and photodehydration of 1-naphthol derivatives in aqueous solution. Can. J. Chem. 2004, 82, 240-253. [Pg.29]

Competitive immunoassays may also be used to determine small chemical substances [10, 11]. An electrochemical immunosensor based on a competitive immunoassay for the small molecule estradiol has recently been reported [11]. A schematic diagram of this immunoassay is depicted in Fig. 5.3. In this system, anti-mouse IgG was physisorbed onto the surface of an SPCE. This was used to bind monoclonal mouse anti-estradiol antibody. The antibody coated SPCE was then exposed to a standard solution of estradiol (E2), followed by a solution of AP-labeled estradiol (AP-E2). The E2 and AP-E2 competed for a limited number of antigen binding sites of the immobilized anti-estradiol antibody. Quantitative analysis was based on differential pulse voltammetry of 1-naphthol, which is produced from the enzymatic hydrolysis of the enzyme substrate 1-naphthyl phosphate by AP-E2. The analytical range of this sensor was between 25 and 500pg ml. 1 of E2. [Pg.143]

They found that the hydrolysis products of 4-AP and 1-naphthol produced well-defined anodic responses at low potentials at a bare SPCE. However, the presence of antibody immobilized on the electrode surface slowed the diffusion of 4-AP towards the electrode surface. In addition, 4-AP may interact with polyphenols on the electrode surface, thus reducing the electroactive working area of the electrode by fouling. In contrast, diffusion of 1-naphthol to the electrode surface was not hindered by immobilized antibody. This feature, along with its low cost, ease of availability, and high solubility, resulted in 1-NP being the preferred AP substrate in their work. [Pg.155]

Salloum M, Dudas M, McGill W (2001) Variation of 1-naphthol sorption with organic matter fractionation the role of physical conformation. Org Geochem 32 709-719... [Pg.142]

The reaction with the siloxy derivative 29 is an interesting example because the product 30 is a 1,5-dicarbonyl derivative (Equation (36)).96 1,5-Dicarbonyls are classically prepared by a Michael addition, but the synthesis of 30 by a Michael addition is not possible because it would require addition to the keto form of 1-naphthol. The acetoxy derivative 31 resulted in a different outcome, leading to the direct synthesis of the naphthalene derivative 32 (Equation (37)).96 In this case, the combined C-H activation/Cope rearrangement intermediate was aromatized by elimination of acetic acid before undergoing a reverse Cope rearrangement. [Pg.180]

The palladium-catalyzed arylation of 2-phenylphenols and naphthols shows an interesting feature of arylation of C-H bonds, leading to the formation of an (aryl)(aryloxy)palladium(n) intermediate.65,65a,65b The phenolates are suitable as precoordinating groups. The reaction of 2-hydroxybiphenyl with an excess of iodobenzene occurs regioselectively at the two ortho-positions of phenyl group under palladium catalysis (Equation (57)). In the case of 1-naphthol, the peri-position is phenylated (Equation (58)). [Pg.227]

Chaudhari et al. (277) had observed a linear dependence of H2O2 selectivity on Ti content in Ti-MCM-41 in the hydroxylation of 1-naphthol to 1,2-dihydroxy naphthalene with aqueous H202 (Fig. 47). Both XAS and EPR results had indicated the presence of mainly the tripodal titanium sites on Ti-MCM-41. As a consequence of the large surface area of the material, these sites are well dispersed, leading to the linear dependence of catalytic activity on Ti content. [Pg.150]

The hydroxy-nitro dye Naphthol Yellow S (6.233 Cl Acid Yellow 1) was discovered in 1879 by Caro and is still manufactured. It is produced by sulphonation of 1-naphthol to give l-naphthol-2,4,7-trisulphonic acid, followed by replacement of the 2- and 4-sulpho groups in nitric acid medium. Nucleophilic substitution of l-chloro-2,4-dinitrobenzene with 4-aminodiphenylamine-2-sulphonic acid gives Cl Acid Orange 3 (6.234). [Pg.352]

In terms of binding energy, classical hydrogen bonding may be enhanced by the increased acidity of the phenolic O—H, if the acceptor alcohol is non-phenolic [149, 182]. On the other hand, n interactions compete with classical hydrogen bonds [19, 54] and may even dominate the interaction, such as in the dimer of 1-naphthol [55]. This is not yet the case for phenol dimer, the prototype compound in this class [246, 247]. [Pg.34]

M. Saeki, S. i. Ishiuchi, M. Sakai, and M. Fujii, Structure of 1 naphthol/alcohol clusters studied by IR dip spectroscopy and ab initio molecular orbital calculations. J. Phys. Chem. A 105, 10045 10053 (2001). [Pg.55]

A. Matsuzaki, S. Nagakura, and K. Yoshihara, Interactions of /1-naphthol and -naphthyl-amine in their excited singlet states with triethylamine, Bull. Chem. Soc. Jpn. 47, 1152-1157 (1974). [Pg.56]

Tremaine LM, Diamond GL, Quebbemann AJ. 1984. In vivo quantification of renal glucuronide and sulfate conjugation of 1-naphthol and p-nitrophenol in the rat. Biochem Pharmacol 33 419-427. [Pg.229]

Condensation of 1-naphthol and hetaryl- or substituted-berrzaldehydes in the presence of ammonia, and subsequent acidic hydrolysis, gave 2 in moderate yields. Reactions of amino naphthols with eqrrivalent amormts of aldehydes resulted in... [Pg.343]

The potential utility of the Mannich-type phenolic bases makes the aminoalkyla-tion reaction of naphthol derivatives a subject of current chemical interest. But, because of the relatively low reactivity of 1-naphthol, the reaction gave only a moderate yield and displayed moderate diastereoselectivity [5]. [Pg.344]

Substituted amino naphthols were synthesized with reactions of 1-naphthols and the appropriate aldehydes. Some new 2,4-disubstituted-3,4-dihydro-2/f-naphth [i,2-e][i,i]oxazines that are expected to show biological activities were obtained by the ring-closure reactions with these aminonaphthols and various aldehydes. In addition, substituted-1,3-amino-hydroxy compounds, 2, can be used in chiral ligands synthesis. [Pg.345]

The appropriate aromatic or heteryl- aldehyde (2 mmol freshly distilled if liquid) and 25% methanolic ammonia solution (5 mL) were added to a solution of 1-naphthol (1 mmol) in absolute MeOH (5 mL).The mixture was left to stand at ambient temperature for 2 days, during which oily products separated. The solvent was evaporated and the crade oily products were purified by column chromatography. The physical data for the compounds la-f are listed Table 39.1. [Pg.345]

In pond water, carbaryl degraded very rapidly to 1-naphthol. The latter degraded, presumably by Flavobacterium sp., into hydroxycinnamic acid, salicylic acid, and an unidentified compound (HSDB, 1989). Four d after carbaryl (30 mg/L and 300 ng/L) was added to Fall Creek water, >60% was mineralized to carbon dioxide. At pH 3, however, <10% was converted to carbon dioxide (Boethling and Alexander, 1979). Under these conditions, hydrolysis of carbaryl to 1-naphthol was rapid. The authors could not determine how much carbon dioxide was attributed to biodegradation of carbaryl and how much was due to the biodegradation of 1-naphthol (Boethling and Alexander, 1979). Hydrolysis half-lives of carbaryl in filtered and sterilized Hickory Hills (pH 6.7) and U.S. Department of Agriculture Number 1 pond water (pH 7.2) were 30 and 12 d, respectively (Wolfe et al., 1978). [Pg.248]

Chemical/Physical Ozonation of carbaryl in water yielded 1-naphthol, naphthoquinone, phthalic anhydride, Wformylcarbamate of 1-naphthol (Martin et al., 1983), naphthoquinones, and acidic compounds (Shevchenko et al, 1982). [Pg.248]

Carbon tetrachloride. Chloroform, 2-Chlorophenol, Cyclohexanol, Cyclopentene, 1,1-Dichloroethylene, irans-l, 2-Dichloroethylene, IV.yV-Dimethylaniline, lV,lV-Dimethylformamide, 2,4-Dimethylphenol, 2,4-Dinitrotoluene, 1,4-Dioxane, 1,2-Diphenylhydrazine, Ethyl formate. Formaldehyde, Glycine, Methanol, Methylene chloride. Methyl formate, 2-Methvlphenol. Monuron, 4-Nitrophenol, Oxalic acid, Parathion, Pentachlorophenol, Phenol, l idine. Styrene, Trichloroethylene, Vinyl chloride Formylacetic acid, see cis-l,3-Dichloropropylene, irans-1,3-Dichloropropylene IV-Formylcarbamate of 1-naphthol, see Carbaryl Formyl chloride, see Chloroethane, Chloroform, sym-Dichloromethyl ether, ds-1,3-Dichloropropylene, irans-ES-Dichloropropylene, Methyl chloride. Methylene chloride. Trichloroethylene, Vinyl chloride lV-Formyl-4-chloro-o-toluidine, see Chlornhenamidine. [Pg.1530]

Fig. 16.20 Fluorescence quenching (FQ) of 1-naphthol in the presence of HA as a function of pH and reaction time (1-naphthol = 8pmol LHA = 11 ppm C ionic strength of O.IM LiQ) F and F denote fluorescence intensities in the absence and in the presence of the quencher (HA), respectively. Reprinted with permission from Karthikeyan KG, Chorover J (2000) Effects of solution chemistry on the oxidative transformation of 1-naphtol and its complexation with humic acid. Environ Sci Technol 34 2939-2946. Copyright 2000 American Chemical Society... Fig. 16.20 Fluorescence quenching (FQ) of 1-naphthol in the presence of HA as a function of pH and reaction time (1-naphthol = 8pmol LHA = 11 ppm C ionic strength of O.IM LiQ) F and F denote fluorescence intensities in the absence and in the presence of the quencher (HA), respectively. Reprinted with permission from Karthikeyan KG, Chorover J (2000) Effects of solution chemistry on the oxidative transformation of 1-naphtol and its complexation with humic acid. Environ Sci Technol 34 2939-2946. Copyright 2000 American Chemical Society...
The reactivity of acyl radicals inside and outside the solvent cage has been a matter of discussion. It has been postulated that aryloxy and acyl radicals could disproportionate within the cage to give phenol (or naphthol) and ketene (37) but the results are not conclusive (Scheme 14). On the one hand, photolysis of 1-naphthyl acetate in a solvent without abstractable H-like Freon 113 (1,1,2-trichl-oro-l,2,2-trifluoroethane) yields low amounts of 1-naphthol (< 0.1%) in comparison with the same reaction in acetonitrile (7%) [50]. This reveals that dispropor-... [Pg.62]

The phenolic oxidative coupling process can also be demonstrated in laboratory experiments. Thus, treatment of 1-naphthol with alkaline potassium... [Pg.341]

In the reaction of 1-naphthol with 3-nitro-4-fluorobenzalmalononitrile in ethanol, catalyzed by secondary amines, nucleophilic displacement of fluorine competes with pyran ring closure. Application of a tertiary amine (N-methylmorpholine) leads to the selective formation of the corresponding aminochromene (94H(38)399). 2,3-, 1,8-Dihydrooxynaphthalenes 148 and 149 react with 1 or 2 equiv. of aromatic aldehyde 28 and MN 27a to yield naphthopyrans 150 and 151 or dipyrans 152 and 153 (90IJB885, 02RCB2238) (Scheme 53). [Pg.210]


See other pages where Of 2-naphthol is mentioned: [Pg.526]    [Pg.498]    [Pg.393]    [Pg.139]    [Pg.376]    [Pg.145]    [Pg.880]    [Pg.21]    [Pg.32]    [Pg.226]    [Pg.815]    [Pg.65]    [Pg.40]    [Pg.133]    [Pg.341]    [Pg.117]   
See also in sourсe #XX -- [ Pg.319 , Pg.331 ]




SEARCH



A Synthesis of 3-Alkyl-l-Naphthols

Asymmetric Catalysis for Oxidative Coupling of 2-Naphthol to BINOL

Asymmetric Oxidative Coupling of 2-Naphthol to BINOL

Asymmetric coupling of 2-naphthol

Benzoylation Reactions of Phenol and Naphthol Derivatives

Catalytic Enantioselective Oxidative Coupling of 2-Naphthols

Catalytic oxidative coupling of 7-Alkoxy-l-naphthols by chiral vanadium complexes

Catalytic oxidative cross-coupling reaction of 2-Naphthol derivatives

Dimerization of 2-naphthol

Enantioselective oxidative coupling of 2-Naphthols catalyzed by a novel chiral vanadium complex

Excited-State Ionization of Naphthol

Formation of Naphthols from Benzenoid Compounds and Alkynes

Oxidative Coupling of 2-Naphthols

Oxidative dimerization of 2-naphthol

Resolution, OF 1,1 -BI-2-NAPHTHOL

Separation of Bi-Naphthol Enantiomers

Stable Radicals of Naphthols

Study 5.1 Mechanistic photochemistry adiabatic proton transfer reactions of 2-naphthol and 4-hydroxyacetophenone

Synthesis of Phenols and Naphthols with Side-chains containing Oxy or Alkoxycarbonyl Groups

© 2024 chempedia.info