YLANG-YLANG OIL. 



83 



The figures given for the percentage of hydroxyl in the seventh column of the 

 table were obtained by the Grignard reaction, in accordance with the method 

 proposed by Zerewitinoff.*" In using this method, methyl iodide dissolved in 

 amyl ether is treated with magnesium and the amount of methane given off by 

 adding an alcohol to the resulting magnesium methyl iodide is measured. This 

 represents the amount of hydroxyl in the added compound, the reaction being : 



ROH+CHjMgl^ CH,+ROMgI. 



The method is exceedingly convenient after the reagent is prepared, it is 

 quick and uses only about 0.2 gram of oil. It bids fair to displace the older 

 method of obtaining the acetyl number. It is well knovtTi that with many 

 - alcohols, as for example with linalool, the standard methods give an acetyl 

 number many percent too low. This new method promises to give more accurate 

 numbers and is so exceedingly convenient that we are noAV testing it thoroughly. 

 The results I have obtained in my first series are as follows : 







Found hydroxyl 

 (per cent). 



Calcuted hydroxyl 

 (per cent). 









10.95 













11.4 







Linaloiil 







11.2 

 ]).3 

 11.1 

 , 11.1 

 11.3 





11.04 



Geraniol 







11.4 

 11.2 

 15.8 





11.04 



Benzyl t 



ileohol 





15.7 

 15.IJ 

 15.0 





15.74 



The formula used in calculating the percentage of hydroxyl is as follows: 



V 

 X (per cent OH) =0.0704- 



where V=volunie of CH^ at 0° and 760 millimeters and S is the weight of 

 substance taken. 



Fraction 1 always presented an odor very much resembling that of amyl or 

 hexyl alcohol. By treating this fraction with benzoyl chloride according to the 

 method of Eaumann-Schotten and redistilling in vacuo, this odor is removed, 

 the fraction then assumes the odor of terpenes and I was able to obtain a few 

 crystals of jiinene nitrosylcliloride melting at 103° from this low-boiling portion. 

 This, together with the o|)tical rotation nf this fraction \v<niM indicate the 

 presence of f/-)iinenp in small quiuitity. The boilini;' poiiil of llic first three 

 fractions indicates that very little pinene is present. A very small percentage of 

 hydroxyl was also found, so that the major part probably consists of other terpenes. 

 The presence of limonene could not be proved. As these terpenes are of no great 

 importance in determining the odor of ylang-j-Iang oil. no further attempts were 

 made to identifv them. 



'Ber. d. chem. Ges. (1901), 40, 2023. 



