130 



AROMATIC ALCOHOLS AND PHENOLS [62 C-63. 



Ann. 281, 96 ; Schiff and Prosio, Gazz. 

 25, 70 : see also Griess and Harrow, Ber. 

 21, 2740). The latter on heating- with 

 alcoholic potash gives the above methyl- 

 cyclohexenone among other products 

 (S. and P. loc. cit, 76), and this can be 

 converted into m-cresol as before. 



[D.] From naphthalene [12] through 

 o-toluic acid (see under benzyl alcohol 

 [54; B,]), and from the latter as under A. 



Phthalic acid may also be converted 

 into phthalimidine (loc. cit.}, the latter 

 nitrated (Honig, Ber. 18, 3447), reduced 

 to 5-amino-o-toluic acid by heating with 

 hydriodic acid and phosphorus (Ibid. 

 3449), and the latter converted into 

 5-hydroxy-o-toluic acid and m-cresol as 

 under A. 



Also from naphthalene through the 

 trisulphonic acids (heteronucleal) derived 

 from the m-disulphonic acid, which, on 

 fusion with alkali, give m-hydroxytoluic 

 acid and m-cresol (Kalle & Co., Germ. 

 Pat. 8 1484 of 1894; Ber. 28,Ref. 694; 

 also Ref. 364). The i : 6-dihydroxy- 

 naphthalene-3-sulphonic acid on fusion 

 with alkali gives the corresponding 

 trihydroxynaphthalene, which yields m- 

 cresol on further heating (Kalle & Co., 

 Germ. Pat. 112176 of 1899 ; Ch. Centr. 

 1900, 2, 700 : see also Ber. 28, Ref. 

 671 and 693, relating to Germ. Pats. 

 81281 and 81333 of 1893 of Meister, 

 Lucius, and Briining, and also Ch. Centr. 

 1897,1, 1039). 



[E.] Ort/iocresol [61J on heating with 

 ammonium chloride and ammonio-zinc 

 chloride at 330-340 gives o-toluidine 

 (Merz and Miiller, Ber. 2O, 547). The 

 latter can be converted into o-toluic 

 acid, and m-cresol as under A. 



Or o-toluidine may be acetylated, 

 nitrated, hydrolysed, and thus converted 

 into 5-nitro-o-toluidine (Beilstein and 

 Kuhlberg, Ann. 158, 345), from which, 

 by the diazo-method, m-nitrotoluene can 

 be obtained (Ibid.}, and from this m- 

 toluidine. The latter might be directly 

 converted into m-cresol by the diazo- 

 method, or indirectly through m-toluic 

 acid, &c., as under A. 



[P.] Paracresol [63] on nitration 

 gives 3-nitro-p-cresol (Armstrong and 

 Thorpe, B. A. Rep. 1875, 112; Hof- 

 mann and Miller, Ber. 14, 573 ; Stadel, 



Ann. 217, 53 ; Frische, Ann. 224, 138), 

 which, by heating with ammonia, gives 

 3-nitro-p-toluidine (Barr, Ber. 21, 1543). 

 The latter can be converted into m- 

 nitrotoluene, m-toluidine, and m-cresol 

 as under A. 



[G.] From benzoic aldehyde [114] 

 through the m-nitro-derivative, m-tolui- 

 dine (see under phenol [60 ; H]), and 

 then as above. 



[H.] From tJiymol [67] by heating 

 with phosphorus pentoxide and decom- 

 position of the m-cresyl phosphate by 

 heating with alkali (Engelhardt and 

 Latschinoff, Zeit. [2] 5, 621 ; South- 

 worth, Ann. 168, 268 ; Stadel and Kolb, 

 Ann. 259, 209 ; Tiemann and Schotten, 

 Ber. 11, 769). 



Or thymol can be converted into 

 thiothymol by the action of phosphorus 

 pentasulphide (Fittica, Ann. 172, 328), 

 3-sulpho-p-toluic acid by oxidation of 

 thiothymol with nitric acid (Ibid. 329), 

 and then through 3-hydroxy-p-toluic 

 acid and m-cresol as under A. 



[I.] From went/tone [129], which gives 

 tetrabrom-m-cresol among the products 

 of the action of bromine. The tetra- 

 brom-derivative gives m-cresol on reduc- 

 tion with sodium in alcoholic solution 

 (Baeyer and Seuffert, Ber. 34, 40). 



[J.] From pulegone [128] through 

 meth} Icyclohexanone (see under phenol 

 [60; S]). The latter gives m-cresol 

 on treatment with a chloroform solution 

 of bromine (Klages, Ber. 32, 2567 : 

 see also Wallach, Ibid. 3338). 



63. Paracresol; 4-Methylphenol. 

 HO 



CH 3 



NATURAL SOURCES. 



Occurs as a salt of cresylsulphuric 

 acid in urine of herbivorous animals, 

 and, in certain diseases, in human urine 

 (Baumann, Ber. 9, 1389; Bladder, 



