the authors, impracticable with exception of the stented process. of Me. I 
upon the use of the above-mentioned spruce turpentine oil. ere 
On the whole, the authors’ process of preparing carvacrol resembles 
1. Formation of cymene-/- -sulphonic acid by treating spruce turpentine il 
 sulphuric- acid; “Sit em 
2. Removal of the excess “alpine acid used in 1. and jormidtidas of calcium cymene 
sulphonate by treatment with finely divided limestone; i 
3. Formation of sodium cymene sulphonate in solution and removal of calefum : as 
carbonate by treating with soda ash; Breen ee wie 
4. Formation of sodium carvacrolate by fusing the sodium cymene sulphonate with 
caustic soda; “ cont 
5. Formation of carvacrol by treating the fusion products of 4. wie sulabubie acid. 
All the materials used in the experimental work were of standard commercial’ purity, — 
such as can always be obtained on the market,’ with the exception of spruce turpentine 4 
oil, which up to the time has had no commercial value. The oil used gave on dist a 
lation the following fractions: below 171.5°, 3.33 per cent. by volume; V1 0 to” 178. 5°, 
83.34 per cent.; above 178.5°, 13.33 per cent. 
When sulphonating, the prime variables are: 1. the strength of the acid; 2. tempo : 
ature; 3. time; 4. proportional amount of acid; 5. amount of stirring, and 6. type, of 
Salpnanatiie vessel. . we Sa OR ANG { 
The adoption of 66° Bé. sulphuric acid as used for the sulphonation a benzene in 
phenol manufacture gave the best results. The most favourable temperature, as. wa 4 
proved in numerous experiments, was between 90 and 100°. As to the time required, 
4 hours were sufficient, provided that intense stirring took place and a temperature of 
96° was maintained. The best method is to sulphonate the spruce turpentine with th 
sulphonation of 300 cc. spruce turpentine with 300 cc. sulphuric acid was complete 
from 3*/, to 4 hours, at 96 to 98°; the iron of the vessel was hardly attacked. W 
sulphonation was complete the mixture separated, on ean into two ae 
place rapidly. In the Baie or on prolonged standing at room semperature ‘aban 
sulphonic acid was separated off from the upper layer as a crystalline substar 
showed the m.p. 50 to 51°, as stated in the literature. Furthermore, the up 
contained small amounts of sulphur. By way of experiment oe amount of W. 
y . rite Sep 
1) Comp. Report April 1915, 50; 1916, 61. The latest investigations seem to prove the. rity 
of American wormseed oil in fighting hookworm disease. Comp. aoe Pp. a ee ae his R 
_ ®) Probably owing to the war. — *%) U.S.P. No. 1265800. ¢ 
