— ii4 — 



It appears that the treatment of a-limonene nitrosochloride with magnesium 

 methyl iodide has given analogous results, as a further work by Til den 

 conjointly with Shepheard 1 ) shows. The body from ^-nitrosochloride 

 recrystallised from alcohol melts at 150 , and is very stable. a-Limonene 

 nitrosochloride, when acted upon by magnesium methyl iodide, yields 

 a body of entirely similar properties; but its melting point (4 2°) lies 

 considerably lower, and it dissolves also more readily in petroleum 

 ether. The analysis showed that both bodies are formed from the 

 corresponding bimolecular nitrosochlorides by loss of an oxygen atom. 

 By the action of molecular quantities phosphorus pentachloride on the 

 a-compound (24 hours at ordinary temperature) a product C 20 H 32 N 2 C1 4 

 of the m. p. 1 3 9° is formed; the corresponding product resulting from 

 the action on the /^-compound melts at 113°. The constitution of 

 the new bodies has not yet been definitely determined. 



Menthene. In a preliminary communication Wallach 2 ) publishes 

 experiments, according to which by condensation of 1, 4-methylcyclo- 

 hexanone with bromo isobutyric ester and zinc, conversion of the 

 oxy ester formed (b. p. 148 to 150 ° at 16 mm. pressure) by loss 

 of water into 1, 4-methylcyclohexene isobutyric ester (b. p. 123 to 

 1 2 6° at 13 mm. pressure), and by saponification of the latter, an acid 

 G 11 H i8 2 melting at 95 to 96 is formed, which on slow distillation 

 with loss of carbon dioxide yields menthene, C 10 H 18 . This hydro- 

 carbon was not, however, the ordinary i-zl3-menthene, but the yet 

 unknown i-zl^-menthene, 



/CH .CH 0V 



ch 3 .ch c:c(ch 3 ) 2 



\ch,.ch/ 





designated by Wallach also as bihydroterpinolene; b. p. chiefly 

 172 to 1 74 ; d 0,831; n D2i° i j4047- By the action of amyl nitrite 

 and hydrochloric acid, an oil with a deep blue colour is formed gradually 

 solidifying into white crystals. The oil as well as the crystals readily 

 volatilise with water vapour. The crystallised addition-product has a 

 melting point of 101 to 103 . Boiling with dilute sulphuric acid con- 

 verts the zl^-menthene into ordinary zl 3 -menthene. 



F. W. Semmler 8 ) conjointly with Ch. Rim pel, has succeeded in 

 synthesising the zJg(9)- menthene and the active A 3, g(9) - menthadiene. 

 The crude material was isopulegol obtained from d - citronellal 

 by Tiemann and Schmidt's method. The former was converted 



*) Journ. Chem. Soc. 89 (1906), 920. 



2 ) Berl. Berichte 39 (1906), 2504. 



3 ) Berl. Berichte 39 (1906), 2582. 



