P 2-naphthoic acid

Diazotise 223 g. of 2-naphtliylamine-l-sulphonic acid as detailed under fi-Bromonaphthalene in Section IV,62. Prepare cuprous cyanide from 125 g. of cupric sulphate pentahydrate (Section IV,66) and dissolve it in a solution of 65 g. of potassium cyanide in 500 ml. of water contained in a 1-litre three-necked flask. Cool the potassium cuprocyanide solution in ice, stir mechanically, and add the damp cake of the diazonium compound in small portions whilst maintaining the temperature at 5-8°. Nitrogen is soon evolved and a red precipitate forms gradually. Continue the stirring for about 10 hours in the cold, heat slowly to the boiling point, add 250 g. of potassium chloride, stir, and allow to stand. Collect the orange crystals which separate by suction filtration recrystallise first from water and then from alcohol dry at 100°. The product is almost pure potassium 2-cyanonaphthalene-l-sulphonate. Transfer the product to a 2-litre round-bottomed flask, add a solution prepared from 400 ml. of concentrated sulphuric acid and 400 g. of crushed ice, and heat the mixture under reflux for 12 hours. Collect the -naphthoic acid formed (some of which sublimes from the reaction mixture) by suction filtration 

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Chapter IV. a-Chloromethylnaphthalene (IV,23) benzylamine (Gabriel synthesis) (IV,39) i r.N -dialkylanilines (from amines and trialkyl orthophosphates) (IV,42) a-naphthaldehyde (Sommelet reaction) (IV,120) a-phenyl-cinnamic acid (Perkin reaction using triethylamine) (IV,124) p-nitrostyrene (IV,129) p-bromonaphthalene and p naphthoic acid (from 2 naphthylamine-1 -sulphonic acid) (IV,62 and IV,164) diphenic acid (from phenanthrene) (IV,165). 

Aryl methyl ketones give generally high yields of acids on treatment with hypohalites [6SS, 696,698, 736. The reaction of 1,3,5-triacetylbenzene and sodium hypochlorite results in a 94% yield of trimesic acid [655], and that of methyl p-naphthyl ketone and sodium hypochlorite gives an 87-88% yield of p-naphthoic acid [695]. 4-Acetyl-4 -methoxybiphenyl is converted... 

Beilstein Handbook Reference) AI3-00894 B.o.n. acid BON BON acid BONA BRN 0744100 Cl Developer 8 Cl Developer 20 CCRIS 2298 Developer 8 Developer BON EINECS 202-180-8 HSDB 5278 2-Hydroxy-3-naphthalenecarboxylic acid 2-Hydroxy-3-naphthoic acid Kyselina 3-hydroxy-2-naftoova Miketazol Developer ONS p-Naphthoic acid, 3-hydroxy- Naphthol B.O.N. Naphthol bon NSC 3719 p-Oxynaphthoic acid. Needles mp = 222.5 Xm = 235, 284 nm (MeOH) slightly soluble in H2O, readily soluble in EtOH, Et20, CeHe, CHCI3, CrH8. 

Xiang, T. and Johnston, K. P. (1997) Acid-Base Behavior in Supercritical Water p-Naphthoic Acid-Ammonia Equilibrium, 7. Solution Chemistry 26, 13-30. 

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