LARCH (VENICE) TURPENTINE 279 



solution, the nitrosochloride melted sharply at 103°, showing this 

 terpene to be a-pinene. While the fraction is levogyrate it contains 

 considerable of the inactive variety for highly active a-pinene does 

 not yield a nitrosochloride.^* 



In the fractional distillation of the oil minute quantities of a crys- 

 talline material collected on the walls of the fractionating column indi- 

 cating the presence of camphene. Attempts to obtain a crystalline 

 product from the various fractions by cooling failed. Fraction 4 was, 

 therefore, tested for camphene by the method of Bertram and Wal- 

 baum.^^ Seventy-five grams of oil were dissolved in 187.5 gm. of 

 glacial acetic acid and heated for three hours at 50 to 60°. The 

 reaction mixture assumed a reddish color but did not become homo- 

 geneous, and the results of the test were negative. 



^-Pincne — Fraction 5 was tested for (3-pinene by oxidation to nopinic 

 acid according to Wallach's directions.^*' Fifty grams of oil were 

 treated with 11 G gm. of potassium permanganate in 1 3^2 liters of water 

 to which 25 gm. of sodium hydroxide had been added. The reaction 

 mixture was shaken for twenty minutes during which time the flask 

 became hot. Steam was then passed through the mixture to remove 

 unchanged oil, 30 gm. of which was obtained. After filtering ofif the 

 manganese dioxide, the filtrate was evaporated to one-third its volume 

 and allowed to cool, when a white flocculent precipitate separated out. 

 The free nopinic acid obtained from this sodium salt melted at 126°, 

 showing (3-pinene to be present in the original oil. 



a-Liuio)iene — Fraction G was found to contain limonene. A portion 

 of the oil was diluted with four volumes of glacial acetic acid, the 

 mixture was cooled, and an excess of bromine was gradually added. 

 No crystals appeared immediately, but after a few drops of water were 

 added and the reaction mixture was allowed to stand for several days, 

 the tetrabrom derivative crystallized out. These crystals melted sharply 

 at 104°. 



The non-volatile residue left after the steam distillation of the oleo- 

 resin gave the constants recorded in table 6 : 



"Journal American Chemical Society, vol. ?,9 (1917). p. 1040. 

 '° Journal fiir praktische Chemie, vol. 49, part II (1S94), p. 1. 

 "Annalen, vol. 356 (1907), p. 228. 



