2-Nitrotoluene CAS 88-72-2

Using 2-Nitrotoluene as raw material, select metal phthalocyanine of general formula (I) structure, mononuclear metalloporphyrin of general formula (II), (III) structure or μ-oxybinuclear metalloporphyrin of general formula (IV) structure any of them 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 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, and the ligand X is chlorine. The amount of catalyst used is 0.2 to 1.0% of the weight of 2-Nitrotoluene, and methanol is used as solvent. In the alkaline methanol solution, 0.8～3.0MPa oxygen gas is introduced, the reaction temperature is controlled to be 25～60°C, and the reaction time is 6～48h to obtain the crude product of o-nitrobenzaldehyde. After separation and purification by conventional methods, o-nitrobenzaldehyde fine products are obtained.

Without any catalyst, 2-Nitrotoluene is used as raw material, oxygen is used as oxidant, sodium hydroxide is used as base, and the reaction temperature is 25~85℃, and the reaction is carried out in solvent alcohol or its aqueous solution for 5~72 hours, and after post-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 2-Nitrotoluene as the raw material, the nitration system of sulfur fuming acid-fuming nitric acid was used to carry out the nitration reaction at room temperature, and 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 include the following steps:

The first step, firstly add fuming sulfuric acid to the reactor, then dropwise add o-nitrotoluene, and then add fuming nitric acid after mixing, and continue the reaction;

In the second step, after the reaction is completed, the mixed solution is poured into crushed ice to separate out a solid. After the ice cubes are completely melted, the solid obtained by suction filtration is 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 2-Nitrotoluene, oleum, and concentrated nitric acid is 1 mol: 0.40~0.65 L: 1~1.05 mol; In the first step, the reaction temperature is maintained at 5 ~ 30 ℃, and the reaction time 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 mode or continuous production mode.