5,7-二羟基黄烷酮的流动氢化仪法合成

针对常规氢化反应釜合成匹诺塞林的合成工艺中容易发生过度还原生成副产物、不易控制反应的进程、重现性差、副产物难纯化分离等问题,为提高匹诺塞林合成收率,利用H-Cube TM流动氢化仪具有连续流动可实时监测从而实现高选择性、反应条件容易优化的特点,以5,7-二羟基黄酮为原料,四氢呋喃为溶剂,还原氢化得到5,7-二羟基黄烷酮.考察了反应液流速、温度、压力对反应收率的影响.结果表明,当反应温度为100℃,压力为2 000kPa,反应液流速为0.5mL/min时,5,7-二羟基黄烷酮的合成收率最高,达到96%,纯度为98.5%.影响黄烷酮合成收率因素顺序为温度>流速>压力.化合物的结构经过熔点、质谱分析法、氢-核磁共振确定,纯度经过液相色谱确证.该方法具有安全、易控制、操作简便、后处理简单等优点,更适合工业化生产.

Synthesis of 5,7-dihydroxyflavanone using H-cube continuous flow reactor

Abstract： To improve the yield of the flavanone and avoid the disadvantages including excessive reduction of by-products, hard to control the reaction process, poor reproducibility and difficult purification in the preparation of pinocembrin by using conventional hydrogenation reactor, an approach to synthesize 5,7-dihydroxyflavanone was investigated with 5,7-dihydroxyflanone as the raw material and tetrahydrofuran as a solvent by using H-Cube TM, this method has advantages of continuous hydrogenation in a flow system, easy monitoring, and rapid optimization of the reaction conditions. The effect of temperature, pressure and flow rate was discussed. The results show that, the 5,7- dihydroxyflavanone yield is up to 96% at the reaction temperature of 100 ℃, pressure of 2 000 kPa and flow rate of 0.5 mL/min. Factors affecting yield is the temperature〉flow rate〉pressure. The structure and purity of 5,7-dihydroxyflavaone is confirmed by m. p. , MS, 1H-NMR and HPLC. This method has the characteristics of safety, easy control and simple operation, which is feasible for industrialization.