60 J-P.] 



PHENOL 



123 



the latter oxidised by permanganate to 

 3-sulphophthalic acid (Remsen and 

 Comstock, Am. Ch. Journ. 6, 107), 

 and the sulpho-acid converted into 3- 

 hydroxyphthalic acid by potash fusion 

 (Remsen and Stokes, Am. Ch. Journ. 

 6 } 282,), and then into phenol as before. 



Or a-naphthol may be sulphonated 

 and nitrated so as to form dinitro-a- 

 naphtholsulphonic (2 :4-dinitro-i-naph- 

 thol-7-sulphonic) acid (Caro, Ber. 14, 

 2029), which on oxidation with nitric 

 acid gives 4-sulphophthalic acid (Graebe, 

 Ber. 18, 1127), from which 4-hydroxy- 

 phthalic acid, m-hydroxybenzoic acid, 

 and phenol can be obtained as above. 



Naphthalene-/3-sulphonic acid, when 

 converted into its amide and the latter 

 oxidised with potassium permanganate, 

 also gives 4-sulphophthalic acid (Remsen 

 and Comstock, Am. Ch. Journ. 5, no). 



[K.] Indigo [Vol. II] on distillation 

 with potash gives aniline (Fritzsche, 

 Ann. 39, 76), which can be converted 

 into phenol as under A. 



[L.] From acetone [106] through 

 mesitylene and uvitic or mesitylenic 

 acid (see under benzyl alcohol [54 ; 

 D]), m-toluic acid or m-xylene (see 

 under o-cresol [61 ; B]), and isophthalic 

 acid by oxidation of either the acid or 

 hydrocarbon (Weith and Landolt, Ber. 

 8, 721 ; Fittig and Velguth, Ann. 

 148, 11). 



Isophthalic acid on nitration gives 

 a mixture of 4- and 5-nitro-acids 

 (Beyer, Journ. pr. Ch. [2] 22, 352; 

 25, 470 ; Storrs and Fittig, Ann. 153, 

 285). The 5-nitro-acid on reduction 

 and application of the diazo-method 

 yields 5-hydroxyisophthalic acid (Beyer, 

 loc. cit. 25, 515), and this gives phenol 

 on heating with lime. 



Or isophthalic acid can be sulpho- 

 nated (Heine, Ber. 13, 493), the 5- 

 eulpho-acid converted into the 5-hy- 

 droxy-acid by potash fusion (Ibid.}, and 

 then into phenol as above. 



Or from acetone through phorone 

 and pseudocumene (see under o-cresol 

 [61 ; B]), methylterephthalic (a-xylidic) 

 acid by oxidising the latter with nitric 

 acid (Fittig and Laubinger, Ann. 151, 

 276), and isophthalic acid, which is 

 formed (with trimellitic acid) by further 



oxidation with potassium permanganate 

 (Krinos, Ber. 10, 1494). 



Or pseudocumene may be sulphonated, 

 the sulphonamide oxidised with alkaline 

 permanganate so as to form 4-sulph- 

 amide-a-xylic acid (Jacobsen and Meyer, 

 Ber. 16, 190), which by further oxida- 

 tion with the same reagent gives 5- 

 sulphotrimellitic acid (Ibid. 192). The 

 latter on potash fusion yields 5-hydroxy- 

 trimellitic acid (Ibid.), and this gives 

 phenol on distillation with lime. 



Or mesitylene maybe sulphonated, and 

 the sulphonamide oxidised with chromic 

 acid mixture or alkaline permanganate 

 so as to form o- and p-sulphamide- 

 mesitylenic acid (Hall and Remsen, 

 Ber. 10, 1040; Jacobsen, Ann. 206, 

 167). The latter acids on further 

 oxidation with potassium permanganate 

 give sulphamidetrimesic acid (Jacobsen, 

 loc. cit. 203), which by potash fusion 

 yields hydroxytrimesic acid (Ibid.), and 

 the latter gives phenol by heating with 

 lime. 



NOTE : Generators of mesitylene and uvitic 

 acid (see under benzyl alcohol [54 ; D to P]) 

 thus become generators of phenol. 



[M.] From cymene [6] through tere- 

 phthalic acid by oxidation (De la Rue 

 and Miiller, Ann. 121, 87 ; Schwanert, 

 Ann. 132, 257 ; Homeyer, Arch. Pharm. 

 [3] 5, 326; Beilstein, Ann.l33,4i). The 

 latter can be converted into nitro- and 

 aminoterephthalic acid by nitration and 

 reduction, and into hydroxyterephthalic 

 acid by the diazo-method (Burkhardt, 

 Ber. 10, 145), the latter giving phenol 

 on heating with sand. 



Or terephthalic acid may be bromi- 

 nated, the bromo-acid fused with potash 

 (Fischli, Ber. 12, 621), and the hydroxy- 

 terephthalic acid thus formed converted 

 into phenol as above. 



[N.] Carvacrol [66] when fused with, 

 potash gives hydroxyterephthalic acid 

 (Jacobsen, Ber. 11, 570), and this can 

 be converted into phenol as above. 



[O.] Thymol [Ql] also gives hydroxy- 

 terephthalic acid when fused with 

 potash (Jacobsen, loc. cit.). 



[P.] Phenylacetic acid [Vol. II] on 

 nitration gives the 2 : 4-dinitro-acid, 

 which can be converted into o-nitro- 



