\ -- ->■'<"• — _ I24 _ 



the desiccator, and it finally separated off small needles in wart- 

 like groups (m. p. 70 to 71 ), which readily dissolve in ether, 

 but with difficulty in petroleum ether. By inoculation with a crystal 

 of the solid bromide, the authors then obtained from the oily product 

 almost quantitatively the solid tetrabromide. They are of opinion that 

 in the analysis of essential oils, more attention should in future be 

 paid to nerol as a constituent, as the number of oils containing nerol 

 is presumably large. 



Now while v. Soden and Treff only deal with constitutional 

 questions in so far, as to seek the difference between the two extremely 

 similar bodies nerol and geraniol in a displacement of the double 

 linking • C : present in geraniol in the two possible directions: — 



CH 3 

 C 3 H 5 • [CH 2 ] 2 . CH : C • C 2 H 4 - OH C 3 H 5 . [CH 2 ] 2 ■ CH 2 - C , C 2 H 4 . OH 



CH 3 and CH, 



a work by O. Zeitschel 1 ) occupies itself with the constitution of 

 nerol as well as with its production from linalool. Based upon older 

 work by Barbier 2 ), Bouchardat 3 ), Bertram and Gildemeister 4 ), 

 and also Stephan 5 ), a new examination of the products resulting 

 from the action of acetic anhydride on linalool proved the fact, 

 which had escaped the earlier investigators, that the latter, as well as 

 geraniol and terpineol, is also isomerised into nerol. Contrary to 

 v. So den's and Treff's view mentioned above, and the same opinion 

 held by Semmler, Zeitschel believes that the difference between 

 geraniol and nerol is caused by different spatial arrangements in the 

 sense of geometrical isomerism with regard to the double-linking which 

 is nearest to the hydroxyl-group in the end-position. The following 

 graphic formulae correspond to Tiemann-Semmler's geraniol formula 

 for the two stereo-isomeric citrals: — 







1. 







II. 







CH 3 . 



C • CH 2 . 



CH 2 . CH 



:C(CH 8 ) 2 



CH 3 .C 



. CH 2 • CH 2 



■CH 



C(CH 3 ) 2 



CHO. 



C-H 







H-C 



• CHO 









(citral a 



= gerania 



I) 





(citral b = 



neral) 





and for 



the two 



corresponding stereo- 



■isomeric 



alcohols: - 











III. 







IV. 







CH, 



t . c . (C: 



H 2 ) 2 • CH: 



C(CH 3 ) 2 



CH 3 . 



C'(CH 2 ) 2 . 



CH : 



C(CH 3 ) 2 



CH 2 (OH) . C • H 







H • 



C • CH 2 OH 









to 



sraniol) 







(nerol) 







x ) Berl. Berichte 39 (1906), 1780. 



2 ) Compt. rend. 116 (1893), 1200. 



3 ) Ibidem, 1253. 



4 ) Journ. f. prakt. Chem. II. 49 (1904), 192; 53 (1896), 225. 



5 ) Journ. f. prakt. Chem. II. 58 (1898),. 109. 



