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2-hydroxy naphthalene 3-naphthol

The nitro substitution products of naphthalene are easily prepared by the action of nitric acid on the hydrocarbon. By such direct nitration the product obtained is alpha-nitro naphthalene. This is proven by the following series of reactions. Nitro-naphfhalene by reduction yields amino naphthalene, naphthylamine, which by the diazo reaction yields hydroxy naphthalene, naphthol. Now the naphthol so obtained is identical with the one resulting from the phenyl vinyl acetic acid synthesis (p. 768) and this must be the alpha compound. [Pg.778]

Trinitro-1-Naphthol (2,4,5-Trinitro-1-hydroxy naphthalene). Yellow leaflets or prisms mp 189—90° bp, explds. Sol in hot AcOH, si sol in hot w, ale, benz, eth acetate, xylene cold AcOH. Prepn from 2,4-dinitro-naphthol by nitration, or from 4-chlor-1,3,8-trinitronaphthalene by heating with 0.1 N NaOH in w or ale... [Pg.202]

Tetranitro-1-Naphthol (2,4,5,7-Tetra-nitro- 1-hydroxy naphthalene). Mp 180°, yellowish leaflets or needles. SI sol in cold AcOH, better in hot AcOH si sol in benz (Ip in 220p benz at 18°). Prepn from 4-brom-l,3,6,8-tetranitro naphthalene by heating on a w bath with an excess of Na carbonate soln. Explds on heating. Forms some expl salts Refs 1) Beil 6, 620 2) V. Merz W. Weith,... [Pg.203]

In much the same way, 2,3-diphenyl-6-quinoxalinamine gave 6-(2-hydroxy-naphthalen-l-ylazo)-2,3-diphenylquinoxaline (substrate, 18% HC1 NaN02/ H20, <5°C, 15 min then solution to ()-naphthol/2.5M NaOH, 30 min —90% analogs likewise).955... [Pg.287]

Trinitro-2-Naphthol (l,6,8-Trinitro-2-hydroxy naphthalene). Light yellow crysts, mp 221°. Prepn from 7-chlor-l,3,8-trinitro-naphthalene by treating with NaOH soln in the presence of acet. Explds on heating Refs 1) Beil 6, (610) 2) E.J. van der... [Pg.204]

The hydroxy naphthalenes are known as naphthols. They possess a phenol-like odor and are exactly analogous to the phenols both in... [Pg.782]

Martius Yellow.—In a similar way the nitro naphthalenes are only faintly colored and are not valuable as dyes while the mixed nitro and hydroxy naphthalenes are colored compounds. One of these is a yellow dye which was formerly used to dye wool and silk but is now principally used in dyeing soaps. It is the 2-4-di-nitro i-naphthol which in the form of its sodium, calcium or ammonium salt is known as Martius yellow. [Pg.785]

Hydroxy-l -naphthaldehyde Naphthalenediols, as antioxidants 899 thermochemistry of 241, 246, 247 N aphthalenes—see Hydroxy naphthalenes, 2-Methoxynaphthalene Naphthazarin, IR spectrum of 383 2-Naphthoates, calix[4]arene-based, photocyclization of 1077 Naphtholate anions 506, 512, 515 1-Naphthol/2-naphthol photoacids 510-520, 523, 524... [Pg.1496]

Naproxen was introduced to the market by Syntex in 1976 as a nonsteroidal antiinflammatory drug in an optically pure form. The original manufacturing process (Scheme 1) before product launch started from P-naphthol (1) which was brominated in methylene chloride to produce 1,6-dibromonaphthol (2). The labile bromine at the 1-position was removed with bisulfite to give 2-bromo-6-hydroxy-naphthalene that was then methylated with methyl chloride in water-isopropanol to obtain 2-bromo-6-methoxynaphthalene (3) in 85-90% yield from p-naphthol. The bromo compound was treated with magnesium followed by zinc chloride. The resultant naphthylzinc was coupled with ethyl bromopropionate to give naproxen ethyl ester that was hydrolyzed to afford the racemic acid 4. The final optically active naproxen (5) was obtained by a classic resolution process. The racemic acid 4 was treated with cinchonidine to fonn diastereomeric salts. The S -naproxen-cinchonidine salt was crystallized and then released with acid to give S -naproxen (5) in 95% of the theoretical yield (48% chemical yield) [8,9]. [Pg.118]

C.l. 76630 CCRIS 7894 1,6-Dihydroxynaphthalene 2,5-Dihydroxynaphthalene EINECS 209-386-7 6-Hydroxy-1-naphthol Naphthalene, 1,6-dihydroxy- 1,6-Naphth-alenediol 2,5-... [Pg.429]

Schaffer s acid, CioHg04S. 2-hydroxy-7-naphthalene sulphonic acid. Obtained by sulphonating 2-naphthol with a small amount of sulphuric acid at a higher temperature than is used for the preparation of crocein acid. A valuable dyestuff intermediate. [Pg.353]

Supplement (combined with Volume XII) XI, 2nd 1933 1605-1739 2. Sulphonic acids Benzenesulphonic acid, 26. p-Toluenesulphonic acid, 97. Naphthalene - sulphonic acid, 155. Hydroxy-Sulphonic acids Phenol-sulphonic acid, 234. Naphthol-sulphonic... [Pg.1121]

The common names for the two hydroxy derivatives of naphthalene are 1 naph thol and 2 naphthol These are also acceptable lUPAC names... [Pg.994]

Fusion/Hydroxylation. The conversion of arylsulfonic acids to the corresponding hydroxy compound is normally effected by heating with caustic soda (caustic fusion). The primary examples are P-naphthol in the naphthalene series and resorcinol in the benzene series further examples are m- am in oph en o1 from metanilic acid and diethyl-y -arninophenol from /V,/V-diethy1metani1ic acid. In the naphthalene series the hydroxy group is much... [Pg.291]

Methyl-[ 5,7-dinitro-8-hydroxy-naphthyl-(l)] -ether, 2,4-Dinitro-8-methoxy-naphthol-(l) ). (02N)2CioH4(OH).O.CH3, mw 264.21, N 10.61%, OB to C02 -121.12%, gold plates from ale, mp 179—80° (decompn). Sol in dil alkali ale. Prepn from 2,4-dinitro-1,8-dime thoxy-naphthalene by reaction with 2N NaOH Ref Beil 6, 5284 ... [Pg.111]

Di n itr o-8- Hyd roxy 1 -Acetoxy-Naphtha bob (2,4-Dinitro-8-acetoxy-naphthol-(l), acetic acid-r >.7-dinit.ro-8-hvdrnxv-nanhthv14r1 V tf rl f5 7. dinitro-8-hydroxy-naphthyl-(l)-acetate]. H0.(O2N)2C10H4.OCOCH3, mw 292.22, N 9.59%, OB to C02 —149.81%, gold prisms from AcOH, mp 200° (decompn). Sol in ale boiling AcOH. Prepn from 1,8-diacetoxy-naphthalene by reaction with dil nitric acid (d 1.4g/cc) at 25-30°... [Pg.202]

This reaction [65-67] is only rarely encountered in the benzene series but is extremely useful for appropriate derivatives of naphthalene, where the mechanism of the reaction has been investigated extensively. The reaction allows a hydroxy group to be exchanged for an amino group or vice versa. When a hydroxy group is to be converted into an amino group, the naphthol is heated under pressure with ammonium bisulphite (often produced in situ by introduction of ammonia liquor and sulphur dioxide into a sealed autoclave) at a temperature of 100-150 °C the naphthol is thereby converted into the corresponding naphthylamine. The mechanism of the reaction is outlined in Scheme 4.22. [Pg.198]

For gas chromatography analysis, samples were spiked with 2-methyl-naphthalene as an internal standard. Samples were analyzed using a Shimadzu GC-17A series gas chromatograph equipped with RTX-5 column, 15 m (length) 0.25 mm (i.d.) and 0.25 pm (film thickness). The initial column temperature was 70 °C and temperature was increased at 20 °C min 300 °C, and column temperature was held for 13 min. Retention times R naphthalene, 3.2 min 2-methyl-naphthalene, internal standard, 4.09 min 1-tetralone, 4.7 min menadione, 5.68 min 1-naphthol, 5.7 min 4-hydroxy-1-tetralone, 6.1 min and 2-methy 1-4-hydroxy-1-tetralone, 6.18,6.27,6.3 and 6.4 min. [Pg.354]

Naphthol Yellow S (citronin A, flavianic acid sodium salt, 8-hydroxy-5,7-dinitro-2-naphthalene sulphonic acid disodium salt) [846-70-8] M 358.2, dec on heating. Greenish yellow powder soluble in H2O. The free sulphonic acid can be recrystd from dil HCl (m 150°) or AcOH-EtOAc (m 148-149.5°). The disodium salt is then obtained by dissolving the acid in two equivalentss of aqueous NaOH and evaporating to dryness and drying the residue in a vacuum desiccator. The sodium salt can be recrystd from the minimum volume of H2O or from EtOH [Dermer and Dermer JACS 61 3302 1939]. [Pg.281]

Condensation of 7-methoxy-3,4-dihydro-1(2H)-naphthal-enone with tetramethylene dibromide by means of NaH in benzene or tert amyl alcohol gives 3,4-dihydro-7-methoxy-2,2-tetramethylene-1(2H)-naphthalene (bp (0,05 mbar) 120-123 °C), which is treated with acetonitrile and butyllithium in THF yielding 1-hydroxy-7-methoxy-1,2,3,4-tetrahydro-2,2-tetramethylene-1-naphthalene-acetonitrile (mp 140-142 °C). This compound is reduced with LiAIH4 in THF to afford hydro-2,2-tetramethylene-1-naphthol (mp 178-180 °C), and isomerized to 4a-(2-aminoethyl)-1,2,3,4,4a,9-hexahydro-6-methoxy-phenantrene i (mp 187 °C). [Pg.176]

Naphthol, 2-naphchol, naphthalene zraw-l,2-dihydrodiol, 4-hydroxy-l-cetralone, 1,2-naphthoquinone, 1,4-naphthoquinone, sulfate and glucuronide conjugates. [Pg.139]

Reaction LVIIL (a) Reduction of Phenols and Quinones by Distillation with Zinc Dust. (A., 140, 205.)—When certain aromatic oxygen compounds (phenols, naphthols, quinones, etc.), are heated with zinc dust, they are reduced to the corresponding hydrocarbons. Thus, phenol yields benzene, the naphthols naphthalene while anthracene can be obtained from anthraquinone or its hydroxy derivatives, alizarin, or quinizarin. In this way alizarin was first proved to be an anthracene derivative. (B., 1, 43.) For catalytic reduction of phenols, see C. r. 193, 1023. [Pg.175]


See other pages where 2-hydroxy naphthalene 3-naphthol is mentioned: [Pg.202]    [Pg.203]    [Pg.497]    [Pg.779]    [Pg.83]    [Pg.714]    [Pg.107]    [Pg.428]    [Pg.291]    [Pg.62]    [Pg.201]    [Pg.68]    [Pg.824]    [Pg.825]    [Pg.825]    [Pg.40]    [Pg.188]    [Pg.140]   
See also in sourсe #XX -- [ Pg.190 ]




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