LECTURE XIV.] HISTORY OF CHEMISTRY. 2QI 



which remove the elements of water. 134 A method of very 

 general applicability is that discovered by Friedel and Crafts, 135 

 which renders it possible, by the help of aluminium chloride, 

 to introduce groups of very different kinds into an aromatic 

 substance, with simultaneous separation of hydrochloric acid 

 or of water, and thus permits the synthesis of hydrocarbons, 

 ketones, acids, etc. 



The possibility of ascending in the series of the primary 

 alcohols, from one term to the next higher term, was shown by 

 the investigations of Pelouze, 136 Kolbe and Frankland, 137 Piria, 138 

 and Wurtz. 139 The desired end is attained by the conversion 

 of the alcohol into cyanide, acid, aldehyde, and alcohol, in 

 accordance with the following equations : 



CNK f C 2 H 5 S0 4 K = C,H 5 CN + SO 4 K 9 

 C,H 6 CN -I- KOH + H,O = C 2 H 5 CO 9 K + NH 3 



C.H-COH {- H 2 = C 2 H 5 CH,OH. 



Lieben and Rossi ascertained the general applicability of 

 the methods. 140 There is also a second mode for obtaining, 

 from one alcohol, the next term in the homologous series, viz., 

 by converting the cyanide (nitrile) into an amine by means of 

 nascent hydrogen (Mendius 141 ), and then decomposing this 

 by means of nitrous acid (Hunt 142 ). A statement has already 

 been made about the synthesis of secondary and tertiary 

 alcohols (pp. 262 and 264). The preparation of the phenols 

 from the hydrocarbons is accomplished by a process which 

 Dusart, Kekule, and Wurtz 143 announced simultaneously. 



Aceto-acetic ether has become of great importance in the 

 synthesis of acids, as aleady stated (p. 264). Malonic ether 144 

 and benzoyl-acetic ether 145 have also been made use of in a 



134 Berichte, 5, 1094. 135 Comptes Rendus. 84, 1392, 1450; 85, 74, 

 etc. 136 Annalen. 10, 249. 137 Ibid. 65, 288 ; see also Fehling, ibid. 

 49, 95. 138 Ibid. IOO, 104 ; compare also Limpricht, ibid, 97, 368. 



139 Ibid. 123, 140. 14 Ibid. 165, 109. 141 Mendius, ibid. 121, 



129. 142 Liebig and Kopp's Jahresbericht 1849, 391. 143 Comptes 

 Rendus. 64. I44 Conrad and Bischoff, Annalen. 204, 121. 145 Baeyer, 

 Berichte. 15, 2705; Baeyer and Perkin, ibid. 16, 2128. 



