71 C-F.] 



QUINOL 



147 



Ann. 12O, 302; Demole, Ber. 7, 1437; 

 Goldberg, Journ. pr. Ch. [2] 19, 368; 

 Hiibner, Ber. 12, 1347; Birnbaum and 

 Reinherz, Ber. 15, 458; Hiibner and 

 Heinzerling, Zeit. [2] 7, 709; Hand, 

 Ann. 234, 133), which on fusion with 

 potash gives 2 : 5-dihydroxybenzoic (5- 

 hydroxysalicylic, gentisic, or 2 :5-phene- 

 diolcarboxylic) acid (Lautemann, loc. cit. 

 311; Liechti, Ann. Suppl. 7, 144; 

 Demole, loc. cit. ; Goldberg, loc. cit. 

 371 ; Miller, Ann. 220, 124 ; Rakowski 

 and Leppert, Ber. 8, 789). The latter 

 on dry distillation yields quinol among 

 other products (Herrmann, Ann. 211, 



Or salicylic acid may be nitrated 

 (Hiibner, Ann. 195, 6; 31 ; Schiff and 

 Masino, Ann. 198, 258 ; Deninger, 

 Journ. pr. Ch. [2] 42, 550; Hirsch, 

 Ber. 33, 3238), the 5- (separated from 

 the 3-) nitro-acid reduced to 5-amino- 

 salicylic acid (Beilstein, Ann. 130, 

 243; Hiibner, Ann. 195, 18; Schmitt, 

 Jahresber. 1864, 383), the latter con- 

 verted into 2 : 5-dihydroxybenzoic ( = 

 gentisie) acid by the diazo-method (Gold- 

 berg, loc. cit. 368), and then into quinol 

 as before. 



NOTE : 5-Aminosalicylic acid is best pre- 

 pared by the reduction of benzeneazosalicylic 

 acid (Fischer and Schaar-Rosenburg, Ber. 32, 

 81). 5-Nitrosalicylic acid also on heating with 

 lime gives p-nitrophenol, which can be reduced 

 to p-aminophenol and treated as above under 

 A. Salicylic acid yields gentisie acid by direct 

 oxidation with potassium persulphate in alka- 

 line solution (Ch. Fab. vorm. Sobering, Germ. 

 Pat. 81297 of 1894 ; Ber. 28, Ref. 692). 



[D.] Benzoic acid [Vol. II] when 

 nitrated gives chiefly m-nitrobenzoic 

 acid (Mulder, Ann. 34, 297 ; Gerland, 

 Ann. 91, 186; Griess, Ann. 166, 129; 

 Hiibner, Ann. 222, 72; Holleman, 

 Zeit. physik. Ch. 31, 79). A solution 

 of this acid in sulphuric acid gives 

 5-aminosalicylic acid on electrolysis 

 (Gattermann, Ber. 26, 1850), and from 

 this 2 : 5-dihydroxybenzoic acid and 

 quinol can be obtained as above. 



m-Nitrobenzoic acid also gives 5- 

 aminosalicylic acid by reduction in 

 strong sulphuric acid with zinc dust 

 at a low temperature (Germ. Pat. 

 96,853 of 1896 ; Ch. Cer.tr. 1898, 2, 

 1 60). 



Benzoic acid also gives among the 

 products of its nitration some o-nitro- 

 acid (Griess, loc. cit. and Ber. 8, 526 ; 

 1O, 1871 ; Ernst, Jahresber. 1860, 299 ; 

 Liebermann, Ber. 10, 862 ; Widnmann, 

 Ann. 193, 204; Holleman, Rec. Tr. 

 Ch. 18, 267), which by reduction gives 

 o-aminobenzoic (anthranilic} add [Vol.11] 

 (Beilstein and Kuhlberg, Ann. 163, 

 138). The latter by the action of 

 potassium emanate [172] on the hydro- 

 chloride yields o-uraminobenzoic acid 

 (Griess, Journ. pr. Ch. [2] 5, 371), and 

 this on nitration gives a dinitro-uramino- 

 benzoic acid (Griess, Ber. 11, 1730), 

 which on boiling with water yields 

 5-nitro-2-aminobenzoic acid (Ibid.}. The 

 latter on heating with potash solution 

 gives 5-nitrosalicylic acid (Ibid.}, which 

 can be treated as under B. 



NOTE : Generators of anthranilic acid [Vol. II] 

 thus become generators of quinol. 



Or benzoic acid may be brominated 

 (Peligot, Ann. 28, 246 ; Angerstein, 

 Ann. 158, 2 ; Reinecke, Zeit. [2] 1, 

 116; 5, 109; Hiibner, Ohly, and 

 Philipp, Ann. 143, 233 ; Hiibner and 

 Petermann, Ann. 149, 131 ; Angerstein, 

 Ann. 158, 5) so as to give m-brom- 

 benzoic acid. The latter on nitration 

 gives (with the 3-brom-2-nitro-acid) 

 3-brom-6-nitrobenzoic acid (Hiibner, 

 Ohly, and Philipp, loc. cit.; Hiibner 

 and Petermann, loc. cit.} } which by 

 reduction yields 6-amino-3-brom- (= 5- 

 brom-2-amino) benzoic acid (H., O., and 

 P. loc. cit. 241), from which by the 

 diazo-method 5-bromsalicylic acid can 

 be obtained (Hiibner and Emmerling, 

 Zeit. [2] 7, 709). The latter can be 

 converted into 2 : 5-dihydroxybenzoic 

 (gentisie) acid, &c., as under C. 



[E.] Cinnamic acid [Vol. II] on nitra- 

 tion gives a mixture of p- and o-nitro- 

 acids (Beilstein and Kuhlberg, Ann. 

 163, 126), from the latter of which 

 o-nitrobenzoic acid can be obtained by 

 oxidation with chromic acid (Ibid. ; 

 Widnmann, Ber. 8, 393), o-aminoben- 

 zoic acid by reduction, and then as 

 under C. 



[P.] Benzole aldehyde [114] on nitra- 

 tion gives chiefly m-nitro-, but also some 

 o-nitrobenzoic aldehyde (Rudolph, Ber. 



L2 



r THI 



WVER8ITY 

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