— 129 — 



Dihydroisophorone yields an a-isoxime of the melting point iii° 

 to H2° and a /?-isoxime of the melting point 82 to 84 . The 

 methyl-(i)-dimethyl-(3)-cyclohexanone-(6)-oxime melting at io8°to 109 , 

 when converted with concentrated sulphuric acid, yields an a-isoxime 

 of the melting point ii5°to 11 6°, and a readily soluble /?-isoxime 

 of the melting point 106 to 108 . 



Phenols and phenol ethers. 



Some few years ago we reported on a method worked out by 

 S. B. Schryver 1 ), for determining phenols in essential oils, according 

 to which sodium amide reacts on phenols in such manner, that the 

 hydrogen of the phenol-group is replaced by sodium, with simultaneous 

 formation of ammonia. The latter is combined with acid and de- 

 termined by titration. Owing to the great reaction-capacity of the 

 amide with water, the method is of course only applicable in the case 

 of absolutely dry mixtures and essential oils. Control-experiments 

 made at the time in our laboratories had given satisfactory results, 

 and we therefore intended making a more extensive use of this method 

 if the occasion should arise. We^also expressed at the time the opinion 

 that this method might possibly become specially important for the 

 quantitative estimation of alcohols, particularly terpene alcohols (linalool, 

 terpineol). In the meantime we have made experiments in this direction, 

 but unfortunately with the result that the method is unserviceable for 

 the determination of alcohols, even for those of the aromatic series, 

 such as benzyl alcohol, etc. In every analysis carried out according 

 to the directions given, the values obtained were much too high, which 

 may possibly be explained by the fact that the sodium amide present 

 in excess in every determination, not only acts in the expected manner, 

 that is to say with formation of one molecule ammonia, but also 

 produces more far-reaching changes in the alcohol molecule, with formation 

 of more ammonia. Now as, according to Schryver's observations, 

 the method can only be applied to oils containing phenols, which are 

 free from ketones and aldehydes, the application of the method in 

 view of our observation with alcohols, would be limited solely to those 

 alcohols which represent mixtures of phenols with terpenes. As a 

 matter of fact, we have obtained satisfactory results in all such cases, 

 as for example with clove oil, pimenta oil, and artificial mixtures. On 

 the other hand, no useful values were obtained in determinations with 

 oil of thyme, where alcohols, such as linalool and borneol, are also 

 present. 



*) Report October 1899, 60; Journ. Soc. chem. Ind. 18 (1899), No. 6. 



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