3 results about "O-nitrotoluene" patented technology

The application discloses a device and method for treating nitro compounds in a gas phase channel of a vacuum concentration device for waste sulfuric acid of polynitrotoluene, wherein the device is supplemented with o-nitrotoluene in the three-stage and four-stage condensers to reduce the freezing point of the acid vapor feed; and the heavy phase containing o-nitrotoluene separated by the three-stage and four-stage condensers is supplemented to the two-stage condenser to reduce the freezing point of the acid vapor feed of the two-stage condenser, thereby solving the problem of nitro compound accumulation in the existing treatment system.

The application discloses o-nitrobenzaldehyde and a synthesis method thereof, and belongs to the technical field of medical intermediates. The synthesis method comprises the following steps: dissolving o-nitrotoluene, dibromohydantoin and azobisisobutyronitrile in mixed organic solvents to perform a bromination reaction, then performing filtration, impurity removal, extraction and organic phase drying in sequence, and separating o-nitrodibromobenzene; adding the o-nitrodibromobenzene into a DMSO solution, adding calcium carbonate to perform an oxidation reaction, then performing filtration, extraction, organic phase drying and purification and decoloration in sequence, and obtaining o-nitrobenzaldehyde. The o-nitrobenzaldehyde is obtained through a bromination oxidation two-step reaction, the synthesis method has the advantages of simple process, low cost, small pollution and high product yield.

The application relates to the technical field of organic synthesis, and particularly discloses a high-efficiency synthesis method of indole-2-carboxylic acid, which comprises the following steps: preparing a high-activity catalyst; preparing a solution containing ethyl nitrophenyl pyruvate by taking o-nitrotoluene and diethyl oxalate as starting materials; adding the solution containing ethyl nitrophenyl pyruvate into a high-pressure kettle, adding the high-activity catalyst, replacing air in the high-pressure kettle with nitrogen, then performing a catalytic hydrogenation reaction, cooling to room temperature after the reaction is completed, filtering the reaction liquid after pressure relief, removing the solvent from the filtrate, and recrystallizing the solid with ethanol to obtain indole-2-carboxylic acid. The application takes o-nitrotoluene and diethyl oxalate as starting materials, synthesizes the target product through two-step reactions, the above conditions are mild and low in cost, the catalyst used in the reaction process is high in catalytic activity, good in cycle stability and easy to recycle.