Naphthyl benzoate

The reaction course has not been elucidated (cf. also sodium hydroxide reagent). Hydrolyzation reactions and aromatizations are probably primarily responsible for the formation of colored and fluorescent derivatives. Substituted nitrophenols - e.g. the thiophosphate insecticides — can probably be hydrolyzed to yellow-colored nitro-phenolate anions by sodium hydroxide or possibly react to yield yellow Meisenheimer complexes. Naphthol derivatives with a tendency to form radicals, e.g. 2-naphthyl benzoate, react with hydrolysis to yield violet-colored mesomerically stabilized 1,2-naph-thalenediol radicals. 

Esterification of aromatic carboxylic acids with phenols, however, cannot be accomplished by a direct esterification procedure and resort must be made to the greater reactivity exhibited by the acid chlorides. Reaction is usually carried out in dilute aqueous alkali (Schotten-Baumann conditions, Section 6.6.2, pp. 916 and 1248). The preparation of 2-naphthyl benzoate is a typical example of this procedure (Expt 6.166). 

Dissolve 7.2 g (0.05 mol) of 2-naphthol in 40 ml of 5 per cent sodium hydroxide solution in the cold add a little more water if necessary. If the solution is highly coloured, add 1.5 g of decolourising carbon and filter the cold solution through a hardened filter paper. Pour the solution into a 100-ml conical flask and run in 7.0 g (5.8 ml, 0.05 mol) of benzoyl chloride. Stopper the flask and shake vigorously until the odour of benzoyl chloride has disappeared (10-15 minutes). Filter off the solid product on a Buchner funnel and wash it with a little cold water. Recrystallise it from about 60 ml of rectified spirit. Filter off the crystals which separate and dry them upon filter paper in the air. The yield of pure 2-naphthyl benzoate, m.p. 110 °C, is 11 g (89%). 

Bromo-2-naphthol with benzoic acid, triphenylphosphine and triethylamine when heated for 3 hours at 150 C afforded a 70% yield of 2-naphthyl benzoate (ref.51). 

Naphthyl benzoate 2-Naphthalenol benzoate CggHggOg 93-44-7 248.276 nd or pr (al) 107.8(0.6) iH2C sEtCH sl eth, HCAc... 

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