The Synthesis Of Dynamics Technology Reseach Of Raspberry Ketone

Via Claisen-Schmidt condensation reaction, raspberry ketone intermediates (p-hydroxybenylbut-3-ene-2-one) was synthesized by using p-hydroxybenzaldenhyde and acetone, catalized by the NaOH aqueous solution. According to the UV spectra absorption characteristics of p-hydroxybenzaldehyde and raspberry ketone intermediates, we established the uv-vis spectrophotometry analysis method which used to detect the content of p-hydroxybenzaldehyde and raspberry ketone intermediates. The UV curve and the linear equations of p-hydroxybenzaldehyde and raspberry ketone intermediates respectively was:A=1.328x105m-0.0767, R2=0.9993, A=1.307×105m-0.0143, R2=0.9984. Compared with the results of the gas chromatography, the precision and stability of UV was better, the sample relative deviation<5.0%.Determine synthesis dynamics of the raspberry ketone intermediates, the results show that the dynamic expression for its apparent level2reaction kinetics equation. The response speed constant of P-hydroxybenzaldehyde were3.400×10-3min-1,4.300×10-3Vin-1,5.200×10-3min-1,6.300×10min-1and7.100×10min-1under20℃,25℃,30℃,35℃and40℃, Ea=24.831 KJ/mol, A=90.423L/(mol·min). So the synthetic dynamic equation of the raspberry ketone intermediates can be expressed as:r=-dt-dCA=90.423eRT-24831CACBThe suitable reaction conditions were obtained by Single factor experiments:the molar ratio of p-hydroxybenzaldehyde are and acetone is1:2.5, the response time4h, reaction temperature30℃, pH=7, the results were consistent with the findings of the dynamics equation. The intermediate is lemon yellow powder solid.The yield amounted to87.51%, intermediates content is98.5%(by GC-MS, area normalization method).Discussed the catalytic effect of load alkali (NaOH/CaO), ion resin (D201,202x7), hydroxyapatite, magnesium aluminum water talc to raspberry ketone intermediates, The liquid chromatographic analysis shows that, the quality score of D201catalytic system intermediates were57.79%.Select the Pd/C and nickelous formate as catalyst to catalized the raspberry ketone intermediates, the result showed that the yield were72.55%catalized by5%Pd/C, hydrogenated time for30min; while the yield were65.7%catalized by nickelous formate, hydrogenated time for30min. The test results of Infrared showed that the product is raspberry ketone.