192 ALDEHYDES AND KETONES : FATTY GROUP [104 C-106. 



ler, Ber. 25, 1180; 26, 2711 ; Bertram 

 and Walbaum, Journ. pr. Ch. [2] 45 



59)- 



1O5. Citron ellal. 

 CH 2 :C.[CH 2 ] 3 .CH.CH 2 .CHO 



CH, 



CHc 



NATURAL SOURCES. 



In citronella oil from the Indian 

 Andropogon nardus (Dodge, Am. Ch. 

 Journ. 11, 460 ; 12, 553 ; Flatau, Bull. 

 Soc. [3] 21, 158: see also Gladstone, 

 Journ. Ch. Soc. 25, 7 ; Wright^ Ibid. 

 27, i ; Pharm. Journ. 5, 233) ; in oils 

 of Eucalyptus maculata, E. citriodora, 

 E. dealbata, and E. planchoniana (Schim- 

 mel's Ber. April, 1888; Oct. 1890; 

 April, 1891; April, 1893; Oct. 1893; 

 Kremers, Am. Ch. Journ. 14, 203 : see 

 also Gildemeister and Hoffmann, p. 702); 

 probably in oil of balm from the S. 

 European Melissa officinalis (Semmler, 

 Ber. 24, 208 : see also Schimmers Ber. 

 Oct. 1 895) and in ( oleum citri ' (Doeb- 

 ner, Ber. 27, 2026). 



The aldehyde occurs to a small extent 

 in lemon-grass oil (Tiemann and Schmidt, 

 Ber. 29, 918; Labbe, Bull. Soc. [3] 

 21, 77), in oil of mandarin orange 

 (Schimmers Ber. April, 1897; Ch. 

 Centr. 1 897, 1, 992), and of sweet orange 

 (Flatau and Labbe, Bull. Soc. [3] 19, 

 361). Citronellal is present in oil of 

 lemon (Schimmel's Ber. Oct. 1902; Ch. 

 Centr. 1902, 2, 1207 : compare Burgess 

 and Child, 'Chemist and Druggist/ 

 60, 812). 



The natural product is d-citronellal. 

 For quantities present in citronella oils 

 from Java and Ceylon see Schimmel's 

 Ber. April, 1900; Journ. Soc. Ch. Ind. 

 19> 556. A 1-citronellal has recently 

 been found in a citronella oil from Java 

 (Schimmers Ber. April, 1903 ; Ch. 

 Centr. 1903, 1, 1086). 



NOTE : The 1-citronellol of oil of rose [38] 

 corresponds with an aldehyde (rhodinal : Bou- 

 veault, Bull. Soc. [3] 23, 458 ; 463^ which is 

 isomeric with the above citronellal and which 

 probably has the constitution : (CH 3 ) 2 : C : 

 CH . H 2 CH 2 CH(CH 3 ) . CH 2 . CHO. An 

 aldehyde of this constitution has been synthe- 



sised from menthone (Wallach, Ann. 278, 302 ; 

 296, 131 ; Harries and Schauwecker, Ber. 34, 

 2981). 



SYNTHETICAL PROCESS. 



[A.] From acetic acid [Vol. II], alcohol 

 [14], and metkylkeptenone [ill] through 

 geranic acid (see under citral [104 ; A]). 

 The latter on reduction with sodium in 

 boiling amyl alcohol gives citronellic 

 acid (Tiemann, Ber. 31, 2901), the cal- 

 cium salt of which on distillation with 

 calcium formate [Vol. II] yields citro- 

 nellal (Ibid. 2902). 



106. Acetone; Dimethyl Ketoiie ; 

 2-Fropanone. 



CH 3 .CO.CH 3 



NATURAL SOURCES. 



Acetone has been found in the dis- 

 tillate from the leaves of Erythroseylon 

 coca ; also in oil of tea (SchimmePs Ber. 

 April, 1898; Ch. Centr. 1898, 1, 991), 

 and (traces) in the ethereal oil (aqueous 

 distillate) from the wood of the Atlas 

 cedar, Cedrus atlantica, and of C. libani 

 (Grimal, Comp. Rend. 135, 582). 



Phaseolunatin, a cyanogenetic gluco- 

 side found in Phaseolus lunatus, is the 

 dextrose ether of acetone-cyanhydrin 

 (Dunstan and Henry, Proc. Roy. Soc. 

 72, 291). 



Acetone occurs in small quantity in 

 the urine of cattle, dogs, and cats ; in 

 human blood and urine, and in larger 

 quantity in cases of diabetes and aceto- 

 nuria. Traces occur in expired air and 

 in emanations from the skin of man 

 (Johannes Miiller, Arch. exp. Path. 40, 

 351 ; Ch. Centr. 1898, 1, 626 : for pro- 

 duction and origin of acetone in the 

 animal organism see Cotton in Journ. 

 Pharm. [6] 10, 193; Ch. Centr. 1899, 

 2, 722 ; Neuberg and Blumenthal, Beit, 

 ch. Physiol. u. Path. 2, 238). 



Acetone has been found in the liquid 

 from a hydatid cyst of the liver (Malme- 

 jac, Journ. Pharm. [6] 13, 406). The 

 acetone in these cases probably results 

 from the decomposition of fat (Schu- 

 mann -Leclerq, Ch. Centr. 1901, 1, 



