BENZENE SERIES. AROMATIC COMPOUNDS. 575 



It is insoluble in water, but soluble in alcohol and in fixed oils. It is non-toxic 

 and non-irritant and is used as a substitute for creosote. 



Guaiacol, C 6 H 4 .OH.OCH ;{ = 123.13, found in beechwood creosote to the 

 extent of from 60 to 90 per cent., is a derivative of the diatomic phenol catechol 

 (pyrocatechin), C 6 H 4 (OH) 2 , obtained from it by replacing a hydroxyl hydrogen 

 atom by methyl, CH 3 . Guaiacol is consequently monomethyl catechol. It is 

 a colorless, crystalline solid, melting at 28.5 C. (83.5 F.), or a colorless re- 

 fractive liquid, boiling at 205 C. (401 F.), and possessing a strong aromatic 

 odor. It is difficultly soluble in water, easily soluble in alcohol and ether. In 

 alcoholic solution ferric chloride produces an immediate blue color, changing 

 to emerald green, later to yellowish. It is obtained either synthetically or 

 from creosote. 



Veratrol, C 6 H 4 (OCH 3 ) 2 , the dimethyl ether of catechol, is a colorless, 

 aromatic, oily liquid, having the same boiling-point as guaiacol. 



A number of derivatives of guaiacol are in the market, being chiefly com- 

 pounds with acid radicals, such as the camphorate (guaiacamphol), carbonate, 

 benzoate (benzosol], cinnamate (styracot), phosphate, phosphite, salicylate 

 (guaiacol-salol), valerate (geosote), etc., one of which is official, namely, 



Guaiacol carbonate, Guaiacolis carbonas, (C 7 H 7 O),.CO 3 , is prepared by satu- 

 rating guaiacol with sodium hydroxide, and treating this compound with car- 

 bonyl chloride, COC1 2 . It is a white crystalline powder, insoluble in water, 

 sparingly soluble in alcohol, soluble in ether and chloroform. 



Creosol, C 6 H 3 .CH 3 .OH.OCH 3 , the second constituent of creosote, is the next 

 homologue to guaiacol i. e., the methyl-ether of dioxytoluene. 



Eugenol, C 6 H 3 (OH)(OCH 3 ).C 3 H 5 . 4 : 3 : 1 = 162.86, is an unsaturated 

 aromatic phenol obtained from oil of cloves and other sources. It is a color- 

 less > or a pale yellow liquid, having a strongly aromatic odor of cloves. 



Safrol, Safrolum, C 6 H 3 .C 3 H 5 .OOCH 2 , 1:3:4 = 180.86 (Shikimol, Allyl- 

 pyrocatcchol methylene ether), is found in oil of sassafras, oil of camphor, and 

 other volatile oils. It is a colorless liquid with a sassafras-like odor. 



Thymol, C 10 H U O or C G H 3 .CH 3 .C 3 H 7 .OH 149.66 (Mdhyl-isopro- 

 pylphenol). Thymol is found in small quantities as a constituent of 

 the volatile oils of wild thyme, horse-mint, and a few other plants. 



Thymol crystallizes in large translucent plates, has a mild odor, a warm, 

 pungent taste, melts at 50 C. (122 F.) and boils at 230 C. (446 F., It is now 

 largely used as an excellent and very valuable antiseptic, preference being 

 given to it on account of its comparative harmlessness when compared with 

 the strongly poisonous carbolic acid. 



Thymol dissolved in moderately concentrated warm solution of potassium 

 hydroxide, gives on the addition of a few drops of chloroform a violet color, 

 which on heating soon changes into a beautiful violet-red. 



Thymol iodide, Thymolis iodidum, (C 6 H,.CH 3 .C 3 H 7 .OI) 2 = 545.76 (Di- 



thymol-diiodide, Aristol, Annidalin}. Obtained by the action of a solution of 



