I9II] Carl L. Aisberg 133 



posed of pinene, which was identified by the preparation of the 

 nitrose-chloride, m.p. 103°. The main fraction was repeatedly dis- 

 tilled and yielded thus an oil boiling at 103-104° under 40 mm., 

 which was found to be thujone by the following constants and deri- 

 vatives : 



D20 0.9152; "D20 1.4530; ^""^ D20 —11.58- 



Derivatives: tribromide, m.p. 121-122°; semicarbazone, m.p. 186- 

 188° (from methyl alcohol) ; tanacetone keto-carbonic acid, m.p. 



75-76°. 



The reaction with hydroxylamine gave an oily oxime which 

 crystalHzed only partially af ter Standing for several months ; which 

 fact, together with the observed levo-rotation — a rotation, it may 

 be noted, sHghtly higher than any previously recorded — further 

 characterized the substance as a-thujone. 



The fraction boiHng from 100 to 103°, 40 mm. (D20 0.8975; 

 "D20 1.4549; ^^-"Dso — 0.62), was tested for fenchone, since that 

 ketone has been isolated from the oil of Thuja occidentalis. Using 

 Wallach's method — oxidation with potassium permanganate, 

 steam distillation, further oxidation with concentrated nitric acid, 

 and recovery of the unaltered fenchone by distillation in steam — 

 only a few drops of oil were obtained which were heavier than 

 water and in which no fenchone was found. An attempt to pre- 

 pare the oxime of the ketone after removal of the thujone by oxi- 

 dation was equally unsuccessful. The authors conclude, there- 

 fore, that fenchone is not present as stated by Brandel (loc. cit.). 



The residue (about 5 per cent.). boiling above 110°, 40 mm. 

 (D20 0.980), was dark brown in color and had an odor of stewed 

 prunes. This was hydrolysed with alcoholic potash, steam distilled, 

 and fractionated. A light yellow oil was obtained whose constants 

 show it to be tanacetyl alcohol (D25 0.9266; "D25 1.46207; 

 b.p.757 210-220°, '^''^D25 + 29.8), probably present as acetate in the 

 original oil. 



From the above results, the authors conclude that the volatile 

 oil of Thuja plicata is composed of 80-85 P^^* cent. thujone, 3-5 per 

 Cent, pinene, 1-2 per cent. tanacetyl acetate, and 1-3 per cent. tant- 

 acetyl alcohol, leaving about 10 per cent. to be accounted for by 

 loss due to formation of resin during distillation and to experi- 

 mental waste. 



