Studies Of Reactions For Drug Synthesis In The Presence Of Transition Metal Under Ultrasound Irradiation

Ultrasound is used more and more frequently in organic synthesis in recent several decades. Compared with non-ultrasounic methods, this new method is more convenient and easily controlled. A great many of organic reactions can be carried out in higher yields, shorter time or milder conditions under ultrasonic irradiation. The dissertation is divided into three chapters:(1) Synthesis of 1,1-diphenylethene under the ultrasound irradiation. The synthesis of grignard reagents and three kinds of 1,1-diphenylethene compounds are studied under the ultrasonic irradiation. Only 15min is needed in preparation of grignard reagents under the conditions that the power of ultrasonic is 250W and frequency is 40KHz, solvent being ether. Furthermore, the optimum technologic conditions of synthesis of 1,1-diphenylethene compounds is the power of ultrasonic is 250W and frequency is 40KHz, ultrasonic water bath temperature being 20℃, solvent being ether without absolutely dry. The yield is 88.2% at least, 30min needed. We can see from that the craft of preparation is simple, reactive time being shorten greatly, only needing simple equipments and the reactive impregnant can used ordinary ether that can not need to be dry under ultrasonic condition.(2) Synthesis of 1,2-dioxanes under the ultrasound irradiation. In order to search for the optimum technologic conditions, many conditions (eg. power, frequency, reaction time, reaction temperature and different mol ratio in reagents) influences on final result were discussed. It can be proved that the reaction time is shortened to 4 hours contrast to over 10 hours in non-ultrasonic condition. The yield raised 10% at the same time. It shows that the power and frequency can bring some influence of the yield in some rule. For this, the optimum technologic conditions of synthesis of 1,2-dioxanes compounds can be shown as that the power of ultrasonic is 400W and frequency is 40KHz, ultrasonic water bath temperature being 23℃, yield is 73.02% in 4 hours.(3) Synthesis of cyclicβ-diketon compounds and study on its reactions under the ultrasound irradiation. A series of cyclicβ-diketon compounds, 1,1-diarylethene and Manganese(III) acetate were synthesized successfully. Furthermore, a series of dicyclic peroxy acetals were synthesized by the radical intermolecular cyclization ofβ-diketon compounds with 1,1-diarylethene in the presence of Manganese(III) acetate in oxygen atmosphere under the ultrasound irradiation (250W, 40KHz) and in non-ultrasound irradiation methods. The object compounds characterized by FTIR and 1H-NMR spectra were same as the compounds received in non-ultrasound irradiation methods. The result shows that ultrasound irradiation can accelerate the cyclization reaction. In contrast, new phenylbenzofuran compounds were synthesized successfully in N2 atmosphere. A new method is provided here for the synthesis of other cyclic peroxy acetals in the present of Manganese (III).