Preparation of 1,4-dichloro-2-nitrobenzene
In a three-necked flask equipped with stirrer, thermometer, and dropping funnel, 147 grams (1.0 mole) of coarsely pulverized p-dichlorobenzene is covered with 300 grams of 100 % sulfuric acid. To this mixture is added with good stirring, over the course of 1 to 1.5 hours, a mixture of 68 grams of nitric acid (d 1.52) and 68 grams of 100 % sulfuric acid. (The acid mixture is prepared by slowly adding the sulfuric acid to the nitric acid with cooling.) When the temperature reaches 30°C. the reaction flask is cooled slightly with water and the addition of acid is regulated so that the temperature remains between 30 and 35° C. The crystals of p-dichlorobenzene gradually melt and when about half of the nitrating mixture has been added, an almost clear, oily layer is formed (eutectic mixture of p-dichlorobenzene and its nitro derivative). Vigorous stirring is necessary to achieve satisfactory mixing. Later, the 1,4-dichloro-2-nitrobenzene begins to crystallize out. This may occur suddenly with the liberation of considerable heat, especially if the stirring has been inadequate, and hence this phase of the reaction should be watched carefully. If a rapid rise in temperature is observed, the addition of the nitrating mixture is interrupted and the cooling is increased in order to keep the temperature below 50° at the most. When the addition of the acids is completed, the reaction mixture is a thick, pale yellow, crystalline mass. Stirring is continued for 3 or 4 hours, the end of the reaction can be determined by diluting a test sample of the reaction mixture with water, filtering off the solid and determining its melting point (56-57°). A mixture of 700 grams of ice and 300 ml. water is now added, and the precipitated material is filtered off with suction and washed with cold water. In order to remove the last traces of acids, the product is melted under 500 cc. hot water, stirred well, and allowed to cool to form a compact cake. This operation is repeated once more, and the acid-free, light yellow, crystalline material is then dried on filter paper at room temperature. The yield of product melting at 56-57° is 186 to 188 grams, or 97 to 98% of the theoretical amount.
The fundamental processes of dye chemistry, by H. E. Fierz-David, 108-109, 1949
1,4-Dichloro-2-nitrobenzene, 2,5-DICHLORONITROBENZENE, 89-61-2, Nitro-p-dichlorobenzene, Benzene, 1,4-dichloro-2-nitro-, 1-Nitro-2,5-dichlorobenzene, 2,5-Dichloro-1-nitrobenzene, 2,5-Dichlornitrobenzen, Benzene, 2,5-dichloronitro-, 2,5-Dichloronitrobenzol, NSC 406125, CCRIS 3096, 1,4-Dichloro-2-nitro-benzene, 2,5-Dichlornitrobenzen [Czech], RZKKOBGFCAHLCZ-UHFFFAOYSA-N, EINECS 201-923-3, BRN 0778109, AI3-01523, Benzene,5-dichloronitro-, WLN: WNR CG EG, Benzene,4-dichloro-2-nitro-, ZINC01693389, PubChem10760, 1,4-dichloronitrobenzene, 2, 5-dichloronitrobenzene, 2,5-dichloro-nitrobenzene, AC1L1NQ4, 1,4-dichloro-2nitrobenzene, DSSTox_CID_31175, UNII-IY18G50FF4, DSSTox_GSID_52602, KSC448I0F, SCHEMBL358730, ACMC-209r21, 225371_ALDRICH, 36572_RIEDEL, CHEMBL354761, IY18G50FF4, 36040_FLUKA, 36572_FLUKA, CTK3E8402, NSC6294, MolPort-002-461-931, Benzene, 1-nitro-2,5-dichloro-, NSC-6294, ZINC1693389, Tox21_303735, ANW-39335, MFCD00007074, NSC406125, SBB064241, AKOS000118944, AS07065, CS21142, MCULE-7128505095, NSC-406125, RP25138, RTR-032870, TRA0009001, CAS-89-61-2, NCGC00357044-01, AC-11511, AJ-30196, AK-94038, AN-42477, CJ-06541, CJ-28319, KB-17889, L086, LS-29810, OR034615, OR095602, SC-26699, ST2408480, TL8005778, TR-032870, D0387, FT-0610319, ST50826761, M-6431, 3B4-3499, I01-4429, W-100368, T0518-0599, InChI=1/C6H3Cl2NO2/c7-4-1-2-5(8)6(3-4)9(10)11/h1-3
C6H3Cl2NO2, CID6977, T1435, 4-05-00-00726 (Beilstein Handbook Reference), 50-44-2