52 BACON. 



The Grignard reaction was conducted in a 400 cubic centimeter bromine flask, 

 in an atmosphere of dry liydrogen. One liundred and fifty cubic centimeters of 

 absolute ether and 7 grams of magnesium filings were placed therein and the 

 reaction was begun with a few drops of ethyl bromide, 45 grams of limonene 

 hydrochloride were then ad<led, wlierenpon the reaction continued, vigorously ; after 

 it was completed the product was poured over cracked ice and dilute sulphuric 

 acid carefully added. The ethereal layer was separated, dried over calcium chlor- 

 ide, the ether distilled and the product finally fraetioned in vacuo with the 

 following results: 



Fraction No. 1: B. P. 100° to 102° at 65 millimeters; 25 grams, chlorine free. 



Fraction No. 2 : 13. P. 102° to 110° at 60 millimeters; 5 grams, containing a 

 trace of chlorine. 



Fraction No. 3 : The residue in the distilling flask, 3 grams, contains a small 

 amount of chlorine. 



Fraction No. 1, was redistilled over sodium at ordinavj' pressure and then 

 yielded 23 grams of an oil boiling between 174° and 176°, with following constants: 



OAO OAo qno 



Specific gravity, ^=0.8257; N^=1.4585; A?^ = 90.3. 



Fractions Nos. 2 and 3 were united and fraetioned over sodium, they gave 3 



grams of an oil passing over between 180° and 210°, containing no chlorine. The 



low boiling portion. No. 1, which posseses an ether-like odor, was again distilled 



at ordinary pressure in an atmosphere of carbon dioxide and 8 grams from the 



middle portion were taken for analysis. The constants of this fraction were: 



30° 

 N ^j:r- = 1.4565; the molecular refraction was M=45.5 calculated for CioHisr=45.3. 



(1) 0.2420 gram substance gave 0.7720 gram CO., and 0.2820 gram H.O. 



(2) 0.1621 gram substance gave 0.5160 gram CO, and 0.1902 gram H.O. 





Found 

 (percent). 



Calculated 

 (percent). 



C 



(1) (2) 

 86.99 86.85 



CioHig Ci„Hic 

 86.96 88.2 



H 



12.98 13.07 



13.04 11.8 



The result leaves little doubt but that the hydrocarbon has the formula 

 CjgHig, but to assure greater certainty it was decided to convert it into 

 the completely reduced substance, CigH^,,. 



This hydrocarbon C'i„H,s, is probably the dihydro-limouene : 



CH, 



and identical with the A^ para menthene which Semmler-' obtained by the 

 = Bcr. d. chem. Ges. (1903),- 36, 1035. 



