Preparation Of Pentahydroxymethyl Furfural And Synthesis Of Phenolic Compounds

Objective:In the decocted fluid of traditional Chinese medicine, usually brings some brown substance, It could be regarded as impurities to remove. This study attempts to break the limitation that people look upon chemical composition from traditional Chinese medicine. We focus on the brown substance; we thought it could be related to 5-HMF and furfural. Then at present, the production process has gradually mature and product could easily be obtained. But the preparation of HMF still kept at the stage of continuous improvement. this experiment studied the sucrose with an appropriate price as the starting material, and the hydrochloric acid as the catalyst, the title compound was synthesized with the dehydration reaction. And synthesized the acetylated product. In addition, we also studied the condensation reaction of furfural and some phenols compounds in the presence of sulfuric acid. Study on Correlation Between the brown substance from traditional Chinese medicine and these colored substances.Methods:Firstly, using two-phase two-solvent immiscible mixtures, 5-hydroxymethyl-2-furfural was synthesized with the dehydration reaction by hydrochloric acid in the water phase contains dimethyl sulfoxide. The yield of 5-HMF is used as a reference standard; Experiment method is employed to investigate some parameters, and find out the optimum formula. And treatment of 5-HMF with acetic anhydride and concentrated sulfuric acid gave the acetylated product. And then, we studied on the aldol condensation reaction similar to the Molish reaction was occurred in furfural,5-HMF and some phenols compounds (such asβ-naphthol, emodin), got their condensation products.Result:The structure of 5-HMF and condensation products were identified successfully by structure analysis of UV、IR、1H NMR、13C NMR、MS spectroscopic. The best synthetically condition was decided by rthogonal and single-factor experiments. The reaction time was100min; the concentration of chloral acid was 6 mol/L; the reaction temperature was 150℃; the solvent volume was 100mL.The yield was 41.6%.When the yield was calculated with the fructose in sucrose, the yield was 76.3%.Conclusion:The result showed that using two-phase two-solvent immiscible mixtures,5-hydroxymethyl-2-furfural was synthesized with the dehydration reaction by hydrochloric acid. This method was simple and feasible, and this method was the first time to use. The structure of condensation products has been confirmed. These products were all the first time to synthesize. Obtained results would provide a solid base for further research.