94 E-95/B.] 



BUTYRIC ALDEHYDE 



183 



193, 104; Schlebusch, Ann. 141, 322), 

 and the a-halo-acid converted into a- 

 hydrox yisovaleric acid = 2 - methyl - 3 - 

 butanolic-4-acid (Fittig and Clark, 

 Ann. 139, 206 ; Schmidt and Sacht- 

 leben, Ann. 193, 106 ; Schlebusch, loc. 

 cit.). The latter gives isobutyric alde- 

 hyde on heating with acids, or by oxida- 

 tion with chromic acid mixture (Ley 

 and Popoff, loc. cit. ; Ley, Journ. Russ. 

 Soc. 9, 131), or with lead peroxide and 

 phosphoric acid (v. Baeyer and H. v. 

 Liebig, Ber. 31, 2110). 



[F.] Leucine [Vol. II], on distillation 

 with water and lead peroxide, gives 

 butyric aldehyde (? normal : Liebig, 

 Ann. 7O, 313). 



[G.] From glycerol [48] and acetone 

 [106] through dimethylallyl carbinol, 

 /3-hydroxyisovaleric acid, ^-dimethyl- 

 acrylic acid, and isobutylene or nitro- 

 isobutylene (see under isobutyl alcohol 

 [18 ; D]), and then as above under D 

 or E. 



[H.] From isoamyl alcohol [22]. Iso- 

 butylene is among the products formed 

 when the vapour of fusel oil is passed 

 through a hot tube (Wurtz, Ann. 104, 

 249 ; Butleroff, Ann. 145, 277 ; Ipatieff, 

 Ber. 35, 1053). 



Or from amyl alcohol through amyl- 

 ene (isopropylethylene) (Eltekoff, Ber. 

 10, 1904 ; Wischnegradsky, Ann. 190, 

 358). Isobutyric aldehyde is among 

 the products of oxidation of this amyl- 

 ene by potassium permanganate (Wag- 

 ner, Ber. 21, 1233). 



[I.] From oxalic acid [Vol. II], ethyl 

 alcohol [14], and isopropyl alcohol [16], 

 through a-hydroxyisovaleric acid by the 

 action of zinc on a mixture of oxalic 

 diethylester and isopropyl iodide, and 

 hydrolysis of the ester thus formed 

 (Markownikoff, Zeit. [2] 6, 517). Sub- 

 sequent steps as under E above. 



[J.] From crotonic aldehyde [102], 

 n-butyric aldehyde being among the 

 products of reduction (Lieben and 

 Zeisel, Monats. 1, 825 ; Charon, Ann. 

 Chim. [7] 17, 223). 



[K.] Isobutylene glycol [47] gives iso- 

 butyric aldehyde on heating with water 

 to 180-200 (Nevole, Ber. 9, 448). 



95. Valeric Aldehyde ; Valeral. 

 C 4 H 9 . CHO 



NATURAL SOURCES. 



A valeric aldehyde is said to occur in 

 the oils of Eucalyptus globulus and of 

 cajeput from Melaleuca leucadendron 

 (Voiry : see under butyric aldehyde [94]) 

 and (isovaleric aldehyde) in American 

 peppermint oil (Power and Kleber, Zeit. 

 anal. Ch. 33, 762; Pharm. Rund. 12, 

 157 ; Arch. Pharm. 232, 639). 



A valeric aldehyde probably occurs in 



the Japanese ' kesso ' oil from the root 



of Valeriana officinalis var. angustl- 



folia (Bertram and Gildemeister, Arch. 



Pharm. 228, 483). 



The oil of Eucalyptus rostrata con- 

 tains a valeric aldehyde (Schimmel's 

 Ber. Oct. 1891). 



SYNTHETICAL PROCESSES. 



/. Normal Valeric Aldehyde ; Peutanal. 



CH 3 .CH 2 .CH 2 .CH 2 .CHO 



[A.] From normal valeric Kadi formic 

 acids [Vol. II] by distilling a mixture 

 of the calcium salts (Lieben and Rossi, 

 Ann. 159, 70 ; Zander, Ann. 224, 81). 



[B.] Succinic acid [Vol. II] is con- 

 verted into thedibromo-acid by bromina- 

 tion (Kekule, Ann. 117, 123 ; Suppl. 1, 

 131 ; Bourgoin, Bull. Soc. [2] 19, 148; 

 Gorodetzky and Hell, Ber. 21, 1731; 

 Lassar-Cohn, Ann. 251, 346). The 

 dibromo-acid, on heating with alcoholic 

 potash, gives acetylenedicarboxylic acid 

 (Bandrowski, Ber. 10, 838; 12, 2212; 

 13, 2340 ; 15, 2694 ; Baeyer, Ber. 18, 

 677 ; 2269), and the latter (or its acid 

 potassium salt), on heating with 

 water, yields propiolic (propargylic = 

 propinic) acid (Bandrowski, Ber. 13, 

 2340), which, by oxidation with cupric 

 hydroxide, is converted into diacetylene- 

 dicarboxylic = hexanediinedicarboxylic 

 acid (Baeyer, loc. cit. 678; 2270). The 

 acid sodium salt of the latter acid on 

 heating in aqueous solution and sub- 

 sequent oxidation of the copper salt 

 with potassium ferricyanide, gives tetra- 

 acetylenedicarboxylic acid (Ibid. 2271), 



