Catalytic Synthesis Of Prenyl Alcohol Process Research

Prenyl alcohol is mainly used for synthesis of intermediates to Methyl-3,3-dimethyl-4-Pentenoate for high efficiency and low toxicity pesticides of the pyrethroid, and its downstream products dichlorochrysanthemate,3-(2,2-Dichlorovinyl)-2,2-dimethylcyclopropanecar bonyl chloride. With prenyl alcohol constantly expanded the scope of application and demand rised ceaselessly, strengthen the study of synthesis for prenyl alcohol, it is very necessary to achieve large-scale industrial production.This paper selects the isoprene and dichloroacetic acid catalytic as raw materials catalytic synthesis for prenyl ester, followed process by saponification reaction preparation of prenyl alcohol. Improved catalytic synthesis process conditions so that the reaction is not under the protection of inert gas, improved the safety and stability of the process. With the rapid development of ethylene industry, the C5as an important byproduct has become the indispensable important resource, using isoprene which is basic chemical raw materials for synthesis of prenyl alcohol, and also the C5resource is efficient used to find a new way.In the process of catalytic synthesis of prenyl alcohol, gas chromatography internal standard curve quantitative analysis of the experimental method is established. With as internal standard, gas chromatographic analysis is made by using PE-FFAP capillary column and programming temperature. The results showed that good separation effect is obtained.The linearity is good for prenyl alcohol.The linear equation is y=1.0408x-0.02359and the linear correlation coefficient is0.99052. The relative standard deviation is0.72%and the average recovery ranged between97.87%-101.07%. Through single factor experiment and orthogonal experiment design, it is obtained the main factor affecting the reaction, and isoprene catalyzed synthesis of prenyl alcohol optimization process condition was established:In the anhydrous system and a10mL as equivalent, proportioning of raw materials is1:2; the reaction time is2h; catalyst amount is1.8g; saponification reaction time is3h; the concentration of NaOH solution is5mol/L.In tne anhydrous system under the conditions of catalytic synthesis of Prenyl alcohol research is based on isoprene and dichloroacetic acid as raw material, sodium of dichloroacetic acid as catalyst under the conditions of the water as a co-catalyst, the study do some research on the catalytic synthesis of Prenyl alcohol. Focus on the acid of raw material ratio, reaction time, amount of catalyst, the saponification reaction time, concentration of NaOH solution, injection volume of distilled water influence on reaction. The experimental results show that, under the conditions of the water as a co-catalyst, the product yield is low, reaching only about26.5%, far below the45%yield of the anhydrous systems.The structure of target product is investigated by means of FTIR and GC, and the product is characterized to determine the target product.