30 results about "Diphenic acid" patented technology

The invention provides a method for synthesizing 4,4'-diphenic acid. In the method, high-boiling-point polyethylene glycol 400 is used as a solvent, cuprous iodide (CuI) is used as a catalyst, and 4,4'-diphenic acid is obtained in the condition of presence of diethylenediamine and potassium hydroxide (KOH) by a reduction coupling new method. The synthesis method has the advantages that the method for synthesizing 4,4'-diphenic acid is simple, the synthesizing condition requirements are not high, the operation is easy, the production cost is low, the yield is very high, the purity is also very high and the repeatability is good, so that the method is suitable for the requirements of large-scale industrialized production; the solvent polyethylene glycol 400 used by the reaction system has high steam pressure, does not pollute the environment and is environment-friendly; and the purification method is simple, column separation purification is not needed, and purification can be carried out just by a common recrystallization method.

The present invention provides a process for the preparation of diphenic acid from phenanthrene which comprises heating phenanthrene and glacial acetic acid, adding dropwise a pre-determined amount of 30 % hydrogen peroxide, heating the resulting mixture after completion of drop wise addition of hydrogen peroxide, distilling the resulting mixture under reduced pressure to make the volume half, cooling the mixture till diphenic acid crystalises out, filtering the cooled mixture and boiling the residue after adding 10 % solution of sodium carbonate and activated charcoal, filtering and discarding the residue; acidifying the filtrate with hydrogen chloride; cooling the resultant mixture till more diphenic acid crystallises out; repeating filtration till pure diphenic acid is obtained.

This invention relates to a method for producing 4-amyl-biphenylcarboxylic acid-3-fluoro-4-cyanophenol ester, comprising: amyl-biphenylcarboxylic acid, thionyl chloride, 3-fluoro-4-cyanophenol, toluene, sodium-hydroxide, and anhydrous ethyl alcohol as raw material, with mole ration as: amyl-biphenylcarboxylic acid 1.05, thionyl chloride 2.65, 3-fluoro-4-cyanophenol 1, toluene 3, sodium-hydroxide 0.1, and anhydrous ethyl alcohol 4.0. The process comprises two steps: (1) use amyl-biphenylcarboxylic acid and thionyl chloride as raw material for acylation reaction and synthesize amyl-bibenzoyl chloride by normal pressure and decreasing pressure distillation; (2) dropwise add amyl-bibenzoyl chloride and 3-fluoro-4-cyanophenol with toluene as solvent for esterification, and produce the target product 4-amyl-biphenylcarboxylic acid-3-fluoro-4-cyanophenol ester by water washing, alkaline washing, crystallization and recrystallization, wherein the conditions: acylation reaction temperature 160Deg C, reflux time 6h, normal distillation temperature 172-176Deg C, pressure decreasing temperature 118-121Deg C, vacuum 50mmHg, the discharging condition is to collect the 3Deg C range product after temperature and pressure stabilized, the temperature of adding 3-fluoro-4-cyanophenol with agitation for acylation reaction is 100Deg C, keep the temperature between 90 and 100Deg C when dropwise adding amyl-bibenzoyl chloride for 3h, reflux with agitation for 6h, heating steam pressure no more than 0.2MPa, autoclave inside temperature kept at 120+2Deg C, crystallization temperature -15Deg C and kept at -15+-2Deg C for 1h for agitation, recrystallization temperature -15Deg Cand kept at -15+-2Deg C for 1h for agitation.