Naphthacyl bromide

Method. The fatty acid (10 jumoles) is dissolved in 1 ml of dimethylformamide. To this solution are added 20 jumoles of 2-naphthacyl bromide and 40 mmoles of ethyldiisopropyl-... 

Fig.4.16. Separation of some 2-naphthacyl esters of fatty adds. A, C, adds B, C adds. Peaks 1 = oleic add 2 = linoleic add 3 a-Unolenic add 4 = 7-linolenic add 5 = dihomo-7-linolenic add 6 = arachidonic add 7 = 2-naphthacyl bromide. (From ref. 40 with permission of the American Chemical Society, Washington.)...

Phenacyl bromide, naphthacyl bromide and their analogues... 

The molar absorption coefficients [72] of some phenacyl and naphthacyl bromides at 2 or the detection wavelength are given in Table 3. To improve the sensitivity and selectivity of the alkylation reaction of carboxylic... 

The following fluorescent alkylating agents have been introduced as pre-chromatographic reagents 9-bromo-methylacridine [480], 3-bromomethyl-6,7-dimethoxy-l-methyl-2(lH)-quinoxalinone [481], naphthacyl bromide (2-bromoacetonaphthone) [482, 483], p-(anthroyloxy)-phenacyl bromide (panacyl bromide) [484], 1-bromo-acetylpyrene [485], 9-chloromethy[anthracene [486], and 9-anthryldiazomethane [487, 488]. 

There have been a number of reagents employed for the esterification of carboxylic acids. 2-Naphthacyl bromide has been used for the esterification of fatty acids and barbiturates (33), the absorption provided by the naphthalene ring giving sensitivity levels of detection of about 4 x 10 g/ml. The benzyl esters of fatty acids have been prepared with the use of l-benzyl-3-p-tolytriazine (34) and the p-methoxyanilides of fatty acids prepared by means of triphenylphosphine (35). The... 

Bromo-l-(2-naphthalenyl)-l-ethanone, 9CI. 2-Bromo-2 -acetonaphthone, SCI. 2-Naphthacyl bromide [613-54-7]... 

Naphtolc Acid (4). 1 and pyndine 2 were heated on a water bath for a short time The product was dissolved in ElOH and precipitated with EtjO Recrystalhzation from 10 volumes ol water affoided pure a-naphthacyl pyndinium bromide 3 A solution of 3 (0 5 g IS mmol) m waler (40 mL), EtOH (12 mL) and 10 N NaOH (2 ml) after healing for 12 min on a waler bath, gave on acidification and extraction with EtzO 4 mp 160-162°C... 

Fatty acids can be derivatized with p-bromophenacyl (73, 85, 86], phenacyl [87-89], naphthacyl [90, 91] or p-nitrophenacyl [74] bromide. To prepare p-bromophenacyl esters [73], fatty acids (0.001—0.5 mM) were dissolved in methanol or water and neutralized to a phenolphthalein end-point by methanolic KOH. The solvent was removed by either a rotary evaporator or lyophilization. A 3—10-fold molar excess of alkylating agent, p-bromophenacyl bromide/18-crown-6 (20 1) in acetonitrile, was then added. The mixture was stirred continuously in a sealed Reacti-Vial at 80 °C for 15 min. After cooling, the solution containing the derivatives was directly subjected to RP-HPLC with UV detection at 260 nm. The mobile phase was usually acetonitrile/ water [87, 92, 93], methanol/water [73, 88, 94, 95] or acetonitrile/methanol/water (86, 89], The separation of phenacyl derivatives of palmitoleic (Ci, ) and arachi-donic ( 20 4) acids was not achieved with the acetonitrile/ water system [87, 89], and elution with methanol/water could not resolve linolenic (Cig.3) and myristic (C]4.q) acids [88, 89]. A ternary mobile phase [89] containing a mixture of acetonitrile, methanol and water seemed to be best for the separation of phenacyl derivatives of fatty acids. 

Carboxylic acids, including formic, acetic, lactic, propionic, malic, tartaric, and citric acids, can be tran.sformed with benzyl, naphthacyl, phenacyl, or bromophenacyl bromides [263], [264] / -nitro-benzyl bromide [265] / -nitrophenacyl bromide methoxyaniline or... 

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