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1- Naphthyl acetate

Naphthyl Acetate. CHgCOOCi H,. Dissolve 1 g. of pure 2-naphtnol in 5 ml. (r8 mols.) of 10% sodium hydroxide solution as before, add 10 g. of crushed ice, and i-i ml. (1-14 g., 1 5 mols.) of acetic anhydride. Shake the mixture vigorously for about 10-15 minutes the 2-naphthyl acetate separates as colourless crystals. Filter at the pump, wash with water, drain, and dry thoroughly. Yield of crude material, 1-4 g. (theoretical). Recrystallise from petroleum (b.p. 60-80 ), from which, on cooling and scratching, the 2-naphthyl acetate separates as colourless crystals, m.p, 71 yield, 10 g. [Pg.110]

P-Naphthyl acetate. Dissolve 5 0 g. of p-naphthol in 25 ml. of 10 per cent, sodium hydroxide solution in a 250 ml. reagent bottle, add 60 g. of crushed ice, and 5-7 g. (5 -5 ml.) of acetic anhydride. Shake vigorously for 10-15 minutes the p-naphth acetate separates as colourless crystals. Filter with suction, wash with water, drain and dry in the air. Recrystallise from light petroleum (b.p. 60-80°) or from dilute alcohol. The yield of pure product, m.p. 71°, is 6-5 g. [Pg.669]

Unusual cyclocarbonylation of allylic acetates proceeds in the presence of acetic anhydride and an amine to afford acetates of phenol derivatives. The cinnamyl acetate derivative 408 undergoes carbonylation and Friedel-Crafts-type cyclization to form the a-naphthyl acetate 410 under severe condi-tions[263,264]. The reaction proceeds at 140-170 under 50-70 atm of CO in the presence of acetic anhydride and Et N. Addition of acetic anhydride is essential for the cyclization. The key step seems to be the Friedel-Crafts-type cyclization of an acylpalladium complex as shown by 409. When MeOH is added instead of acetic anhydride, /3,7-unsaturated esters such as 388 are... [Pg.344]

Naphthylacetic acid derivatives, showiag antiinflammatory, analgesic, and antipyretic activities ate prepared by Ftiedel-Crafts acylation of methyl 1-naphthyl acetate at the 4 position with (CH2)2CHCOCl followed by Clemmensen reduction (97). [Pg.558]

Naphthalene, 216 Naphthalene picrate, 217 Naphthalene sulphonaie ofsodiiim, 218-/ J-Naphthol, 219 Naphthol yellow, 224 /i Naphthyl acetate, 222 /j-Naphthyl methyl ether, 220 /-Nitracetanilide, 153 w-Nitraniline, 154 /-Nitraniline, 153 Nitric acid (fuming), 22 NitroVienzene, 142 w-Nitrobenzoic acid, 200 Nitrogen, qualitative e rimation, 2 quantitative estimation, 13 Nitrophenol, 183 Nitrosohenzene, 146 /-Nitrosodimethylaniline, 157 Niirosoplienol, 159... [Pg.355]

Trinitro-5-hydroxy-l-acetoxy-naphthalene, acetic acid-[2,6,8-trinitro-5-hydroxy-1 -naphthyl-ester], [2,6,8-trinitro-5-hyd roxy-1 -naphthyl] -acetate). (O2N)3C10H3(OCOCH3).OH, mw 337.22, N 12.46%, OB to C02 -87.78%, yellow needles... [Pg.202]

Identical kinetics are exhibited in the analogous oxidations of 1- and 2-methoxynaphthalene to 4-methoxyl-l-naphthyl acetate and 2-methoxy-1,4-naphthoquinone respectively . In these cases the radical-cations may react with acetate ion thus... [Pg.406]

Chohnesterase-inhibiting pesticides (e g., organophosphate and carbamate pesticides) are detected by dipping the developed chromatogram in a solution of the enzyme chohnesterase followed by incubation for a short period. Then the plate is dipped in a substrate solution, e.g., 1-naphthyl acetate/fast blue salt B. In the presence of the active enzyme, 1-naphthyl acetate is hydrolyzed to 1-naphthol and acetic acid, and the 1-naphthol is coupled with fast blue salt B to form a violet-blue azo dye. The enzyme is inhibited by the pesticide zones, so the enzyme-substrate reaction does not occur pesticides are, therefore, detected as colorless zones on a violet-blue background [36]. [Pg.182]

In 1982, the Schaap group demonstrated that chemiluminescence can be induced by the addition of a base to dioxetanes bearing a phenolic substituent [11]. Herein, the same group presents a method utilizing aryl esterase to catalyze the cleavage of a naphthyl acetate-substituted dioxetane in aqueous buffer at ambient... [Pg.532]

An early, qualitative observation of the exceptional reactivity of phenyl and naphthyl acetates having proximate formyl groups was made in 1946 (Vavon and Scandel, 1946). A quantitative study of the alkaline hydrolysis of the 2-, 3- and 4-formylphenyl acetates was made by Holleck et al. (1958). The 2-formyl ester [39] was very rapidly hydrolysed compared with the 3- and... [Pg.191]

A few acetates of phenols have been used extensively as probes to investigate esterases, e.g., phenyl acetate (7.15), 4-nitrophenyl acetate (7.16), a-naphthyl acetate (7.17) and 7-acetoxy-4-mc(hyl-27/-[l bcnzopyran-2-onc (4-methylumbelliferyl acetate, 7.18). Such substrates are easy to handle and their phenolic metabolite is readily analyzed, allowing convenient monitoring of the reaction. [Pg.392]

Methoxy-2-(l-naphthyl)propionic acid, 2-methoxy-2-(l-naphthyl)acetic... [Pg.86]

Reactions of a wide range of substituted phenyl acetates with six a-effect nucleophiles have revealed little or no difference, compared with phenolate nucleophiles, in the values of the Leffler parameters. As a result, the case for a special electronic explanation of the a-effect is considered unproven. Studies of the kinetics and mechanism of the aminolysis and alkaline hydrolysis of a series of 4-substituted (21) and 6-substituted naphthyl acetates (22) have revealed that, for electron-withdrawing substituents, aminolysis for both series proceeds through an unassisted nucleophilic substitution pathway. [Pg.40]

The late discovery of acetyl xylan and feruloyl esterases has been partly due to the lack of suitable substrates. Xylans are often isolated by alkaline extraction, in which ester groups are saponified. Treatment of plant materials under mildly acidic conditions, as in steaming or aqueous-phase thermomechanical treatment, leaves most of the ester groups intact. These methods, however, partly hydrolyze xylan to shorter fragments (63,69). Polymeric acetylated xylan can be isolated from delignified materials by dimethyl sulfoxide extraction (70). The choice of substrate is especially important in studies of esterases for deacetylation of xylans. The use of small chromophoric substrates (p-nitrophenyl acetate, a-naphthyl acetate, and methylumbelliferyl acetate) analogously to the assays of disaccharidases may lead to the monitoring of esterases unable to deacetylate xylan (33, 63, 64). [Pg.431]

The implication of a singlet excited state in the PFR seems now well established if considering the overwhelming evidences however, some recent studies point that in certain cases the rearranged products could arise from upper triplet states [26,27], This contribution is usually minor. For the case of 1-naphthyl acetate, it has been estimated that less than 10% of the rearranged photoproducts have a triplet origin. [28]. [Pg.49]


See other pages where 1- Naphthyl acetate is mentioned: [Pg.70]    [Pg.545]    [Pg.545]    [Pg.665]    [Pg.789]    [Pg.789]    [Pg.568]    [Pg.568]    [Pg.306]    [Pg.306]    [Pg.222]    [Pg.222]    [Pg.263]    [Pg.175]    [Pg.910]    [Pg.727]    [Pg.728]    [Pg.665]    [Pg.789]    [Pg.789]    [Pg.195]    [Pg.964]    [Pg.282]    [Pg.837]    [Pg.837]    [Pg.394]    [Pg.394]    [Pg.404]    [Pg.200]    [Pg.1273]   
See also in sourсe #XX -- [ Pg.336 ]




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2-Naphthyl

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