202 



ALDEHYDES AND KETONES : FATTY GROUP [109-111 A. 



377; 1026; Ch. Drug. 6O, 304; 

 Power and Lees, Trans. Ch. Soc. 81, 

 1588). 



The ketone occurs also in the essen- 

 tial oil of lime leaves from Citrus limetta 

 (Watts, Trans. Ch. Soc, 49, 316). 



SYNTHETICAL PROCESSES. 



[A.] From octyl alcohol [28] and 

 acetoacetic acid (eater) [Vol. II]. The 

 alcohol is converted into n-octyl iodide 

 (Zincke, Ann. 152, 3 ; Moslinger, Ann. 

 185, 55), and the latter by interaction 

 with sodio-acetoacetic ester gives octyl- 

 acetoacetic ester (Guthzeit, Ann. 204, 

 2), which, on decomposition with alco- 

 holic potash, yields the ketone (Ibid. 4). 



[B.] From acetic and decoic acids 

 [Vol. II] by the dry distillation of 

 a mixture of the calcium salts (Gorup- 

 Besanez and Grimm, Ann. 157, 275; 

 Ber. 3 } 518). 



11O. Metliyl-ii-clecyl Ketone ; 

 2-Dodecaiione. 



CH 3 .CO.[CH 2 ] 9 .CH 3 



NATURAL SOURCE. 



Possibly in oil of rue with the pre- 

 ceding ketone (references as under 

 undecanone [109] above). 



SYNTHETICAL PROCESSES. 



[A.] From acetic and lauric acids 

 [Vol. II] through methylundecyl ketone 

 (2-tridecanone) by distilling a mixture 

 of the barium salts (Krafft, Ber. 12, 

 j 667). This ketone on oxidation gives 

 (with acetic acid) undecanoic acid (Ibid.}, 

 the barium salt of which, on distillation 

 with barium acetate, yields 2-dodecanone 

 (Ibid. 15, 1708). 



NOTE : The identity of the natural with the 

 artificial product requires confirmation. 



111. Metliyllieptenone ; 

 2-Methyl-2-heptene-6-one. 



(CH 3 ) 2 : C : CH . CH 2 . CH 2 . CO . CH 3 



NOTE : For constitution see Tiemann and 

 Semmler, Ber. 26, 2721; 28, 2128; Harries, 

 Ber. 5, 1179. 



NATURAL SOURCES. 



In lemon-grass oil (Barbier and 

 Bouveault, Comp. Rend. 118, 983 ; 

 Bertram and Tiemann, Ber. 32, 834), 

 in oil of Mexican ' lignaloe' (Schimmel's 

 Ber. April, 1892; Oct. 1894; Barbier 

 and Bouveault, loc. cit. 121, 168), and 

 in citronella oil (Schimmel's Ber. April, 

 1 895). In oil of lemon (Ibid. Oct. 1 902 ; 

 Ch. Centr. 1902, 2, 1207). 



The ketone is probably present in 

 other essential oils containing geraniol, 

 linalool, and citral (see Tiemann, Ber. 

 31, 3286). 



SYNTHETICAL PROCESSES. 



[A.] From metJiyl and ethyl alcohols 

 [13 ; 14], aceiic and propionic acids 

 [Vol. II], and acetone [106]. Di- 

 methylethyl carbinol is prepared by 

 the interaction of zinc methyl and 

 propionyl chloride (Popoff, Ann 145, 

 292 ; Jermolajeff, Zeit. [2] 7, 275 ; 

 Wischnegradsky, Ann. 19O, 336). On 

 bromination this alcohol gives as chief 

 product the amylene bromide, (CH 3 ) 2 : 

 CBr . CHBr . CH 3 = 2 : 3-dibroin-3- 

 methylbutane, which by the extreme 

 action of alcoholic potash is converted 

 into dimethylallylene = 3-methyl- 1 : 2- 

 butadiene (see under acetone [106 ; B], 

 and Ipatieff, Ber. 29, Ref. 91). The 

 latter, on combination with hydrogen 

 bromide, gives the amylene bromide, 

 (CH 3 ) 2 : CBr . CH 2 . CHJBr = /3-di- 

 methyltrimethylene bromide =1:3- 

 dibrom-3-methylbutane (Ipatieff, loc. cit. 

 92). The latter reacts with sodio- 

 acetylacetone to form a diketone, 

 (CH 3 ) 2 : C : CH . CH 2 . CH(CO . CH 3 ) 2 , 

 which, on decomposition with strong 

 caustic soda solution, yields (with acetic 

 acid) a small quantity of methyl- 

 heptenone (Barbier and Bouveault, 

 Comp. Rend. 122, 1423). 



NOTE : Acetylacetone is obtained by the 

 action of sodium on a mixture of acetone and 

 ethyl acetate (Claisen and Ehrhardt, Ber. 22, 

 ion ; also Germ. Pat. 49542 of 1899 : see a ' so 

 under n-primary amyl alcohol [20 ; B and C]). 



The dimethylethyl carbinol may also 

 be prepared from the amyl alcohol of 

 fusel oil [22] through the correspond- 



