A thiophenol, C 6 H 5 SH, is known, and is prepared by the action of phosphorus pentasulphide on phenol, or by distilling a mixture of sodium benzene sulphonate and potassium sulphydrate.
a-Naphthol may be prepared by fusing sodium-a-naphthalene sulphonate with caustic soda; by heating a-naphthylamine sulphate with water to 200° C. (English Patent 14301 (1892)); and by heating phenyl isocrotonic acid (R.
0-Naphthol, C 1 oH 7 OH, prepared by fusing sodium 0-naphthalene sulphonate with caustic soda, crystallizes in plates which melt at 122° C. With ferric chloride it gives a green colouration, and after a time a white flocculent precipitate of a dinaphthol.
a-Naphthoic acid, C 1 oH 7 CO 2 H, is formed by hydrolysis of the nitrile, obtained by distilling potassiuma-naphthalene sulphonate with potassium cyanide (V.
Chemie, 1868, p. 34), or by heating the sulphonate with sodium formate (V.