2-Nitrotoluene CAS 88-72-2

Take o-nitrotoluene as a raw material, select any one of metal phthalocyanine, mononuclear metalloporphyrin or μ-oxygen binuclear metalloporphyrin as a catalyst, in the formula, M1, M2, M3, M4, M5 are transition metal atoms , M1=Fe, Co, Cu, Zn, M2=Fe, Mn, Co, Cu, Zn, M3=Fe, Mn, Co, M4 and M5 can be the same or different, when they are the same, M4=M5=Fe, Mn, Co, different, M4=Fe, M5=Mn or M4=Fe, M5=Co, R can be carboxyl or hydrogen, R1, R2 can be hydrogen, halogen, nitro, hydroxyl, alkoxy, The ligand X is chlorine, the amount of the catalyst is 0.2-1.0% of the weight of o-nitrotoluene, methanol is used as a solvent, and 0.8-3.0 MPa of oxygen is introduced into 3.0-6.0 mol/L strong basic methanol solution, The reaction temperature is controlled to be 25-60° C., and the reaction time is 6-48 h to obtain crude o-nitrobenzaldehyde. After separation and purification by conventional methods, o-nitrobenzaldehyde fine products are obtained.

Without adding any catalyst, using o-nitrotoluene as raw material, oxygen as oxidant, sodium hydroxide as alkali, the reaction temperature is 25-85 ℃, and the reaction is carried out in solvent alcohol or its aqueous solution for 5-72 hours. Treatment, separation and purification to obtain the o-nitrobenzoic acid. The method requires no catalyst; the raw materials and solvents are cheap; the reaction temperature is moderate; the production control is easy, the yield can be as high as 90%, and it is suitable for mass preparation and industrialization, and has broad application prospects.

Using o-nitrotoluene as raw material, using fuming acid sulfur-fuming nitric acid nitration system to carry out nitration reaction at room temperature, the dinitrotoluene mixture was obtained in high yield. The proportion of 2,4-DNT in the dinitrotoluene mixture can reach 75%. By adopting the nitration reaction at room temperature, the generation of trinitrotoluene is avoided, and the safety of the nitration process is improved.

Specifically, it includes the following steps: in the first step, add fuming sulfuric acid to the reactor first, then add o-nitrotoluene dropwise, and then add fuming nitric acid after mixing evenly, and continue the reaction; in the second step, after the reaction is completed, add the mixed solution Pour into crushed ice to precipitate solids. After the ice cubes are completely melted, the solids obtained by suction filtration are washed with hot water, cooled, suction filtered, and dried to obtain dinitrotoluene.

Wherein, the mass fraction of sulfur trioxide in the oleum in the first step is 5~25%; the consumption ratio of o-nitrotoluene, oleum, concentrated nitric acid is 1 mol: 0.40~0.65 L: 1~1.05 mol In the first step, the temperature of reaction is maintained at 5～30 ℃, and the reaction times is 2～3h; In the second step, the mass fraction of 2,4-dinitrotoluene in the obtained dinitrotoluene is 72～75% ; The nitrification process adopts discontinuous production or continuous production.