Abstract:

A series of imidazole[4,5f][1,10]phenanthroline and its derivatives were synthesized using 1,10-phenanthroline and various benzaldehydes and substitute benzaldehydes as raw materials in Pyrex reactor through application of microwave-assisted heating technology with the yield of 52%-89%, and the target compounds were characterized and in agreement with that of literature. The orthogonal test methods were used to optimize the synthesis conditions of PIP and the results indicated that the yield of PIP will reach to 89% under the irradiation of microwave for 20 min at 100℃ with a reactant ratio of n(phenanthroline): n(benzaldehydes)=1.0: 1.5. Compared with the conventional synthesis method, microwave-assisted synthesis offers a simple feasible method to synthesize imidazole[4,5f][1,10]phenanthroline and its derivatives with high yield in a short time. Further studies on the synthesis of p-BrPIP in SiC vial, which adsorb the microwave and transfer it to heat instantly, showed a reducing yield but improving stability of the reaction compare to that in prexy vial attributed to the nonthermal effect of microwave.

Key words: Imidazole[4,5f][1,10]phenanthroline, Microwave irradiation, Condition optimization, Microwave nonthermal effect