116-117 E.] 



viridis (Ibid. Oct. 1901), and E. hemi- 

 phloia (Ibid. April, 1892). 



NOTE : According to H. G. Smith (Proc. 

 Roy. Soc. N. S. Wales, 34) the aldehyde of 

 Eucalyptus oils is not curaic aldehyde, but a new 

 aldehyde, ' aromadendral.' 



Cuminal is contained in Ceylon oil 

 of cinnamon (SchimmeVs Ber. April, 

 1902 ; Walbaum and Hiithig, Journ. 

 pr. Ch. [2] 66, 55). 



SYNTHETICAL PROCESS. 



[A.] Cymene [6] on chlorination at 

 its boiling- point gives i^chlorcymene 

 = cymyl chloride (Errera, Gazz. 14, 

 277). The latter yields cuminal on 

 boiling with lead nitrate and water 

 (Ibid. 278). A small quantity of the 

 aldehyde is obtained by the oxidation 

 of cymene with sulphuric acid and 

 manganese dioxide (Fournier, Comp. 

 Rend. 133, 634). 



CUMIC ALDEHYDE 



213 



117. Salicylic Aldehyde ; 



Orthohydroxybenzaldehyde ; 



Orth.ohydroxyph.enal ; 



2-Fhenolmethylal. 



CHO 



/\ 



OH 



NATURAL SOURCES. 



The complex is contained in some 

 compound present in the flowers and 

 herb (but not in the root) of Spiraa 

 itlmaria (Pagenstecher, Berz. Jahresber. 

 18, 336 ; Lowig, Ibid. 20, 355 ; Pogg. 

 Ann. 36, 383; Dumas, Ann. 29, 306; 

 Ettling, Ibid. 309 ; 35, 247) ; in the 

 herbs of Spircea digitata, S. lobata, and 

 S.filipendula; in the flowers of S. aruncus 

 (Wicke, Ann. 83, 175), and in the root 

 and stem of hawk's-beard, Crepisfcetida 

 (Wicke, Ann. 91, 374). The glucoside, 

 spirsein, contained in the old roots of 

 Spirfea kamsckatica is a glucoside of 

 salicylic aldehyde (Beyerinck, Centr. 

 Bakter. II, 5, 425 ; Ch. Centr. 1899, 

 2, 259). 



Mould fungi (Aspergillus oryzce) split 

 off saligenin from salicin [157], and then 

 oxidise the alcohol to the aldehyde 

 (Brunstein ; Abst. in Journ. Fed. Inst. 

 7, 3 6 7 ; 8, 507). _ 



The aldehyde is said to have been 

 obtained from the larva and imago of 

 the beetle, Chrysomela populi (Jahresber. 

 1850, 583 ; Enz, Ibid. 1859, 312). 



SYNTHETICAL PROCESSES. 



[A.] From phenol [60] (with p- 

 hydroxybenzaldehyde) by heating with 

 chloroform [l ; D] in presence of sodium 

 hydroxide solution(Tiemann and Reimer, 

 B"er. 9, 423 ; 824). 



Or from phenol and ethyl alcohol [14] 

 through coumarone (see under phlorol 

 [64 ; C]). The latter on nitration 

 gives a nitrocoumarone, which yields 

 salicylic aldehyde among the products 

 of its decomposition by sodium ethylate 

 (Stoermer and Richter, Ber. 30, 2094 ; 

 Stoermer and Kahlert, Ber. 35, 1640). 



[B.] Saligenin [55] gives salicylic 

 aldehyde on oxidation (Piria, Ann. 30, 



153). 



[C.} Salicin [157] gives salicylic 

 aldehyde on oxidation with sulphuric 

 acid and potassium dichromate, &c. 

 (Piria, loc. cit. ; Schiff, Ann. 150, 193; 

 210, 115). 



[D.] Acetophenone (see under benzoic 

 aldehyde [114 ; A ; G, &c.]) on nitra- 

 tion at a low temperature gives (with 

 m-nitro-) o-nitroacetophenone (Engler, 

 Ber. 18, 2238 ; Camps, Arch. Pharm. 

 240, 6), and this on reduction yields 

 o-aminoacetophenone (Gevekoht, Ann. 

 221, 326 ; Camps, loc. cit. 15). By 

 the diazo-method the latter is converted 

 into o-hydroxyacetophenone [130] (Fried- 

 lander and Neudorfer, Ber. 30, 1080 ; 

 Dunstan and Henry, Trans. Ch. Soc. 75, 

 71). The hydroxy-ketone by acetyla- 

 tion and bromi nation gives acetyl-o- 

 hydroxy-co-acetophenone bromide, which, 

 on boiling with water and chalk, yields 

 ketocoumaran = coumaranone [132] (F. 

 and N. loc. cit. 1081). The latter on 

 heating in alkaline solution gives sali- 

 cylic aldehyde (Ibid.}. 



[E.] From cinnamic acid [Vol. II] 

 through o-nitrocinnamic acid and ester 



