Study On Synthesis And Properties Of Ferrocenyl-pyrazoline Derivatives

In this paper, ferrocene group was introduced into pyrazoline compounds, some novel pyrazoline derivatives containing ferrocene were synthesized, and the structure, ultraviolet absorption, fluorescence emission and the electrochemical properties of the target compounds were studied. It has unique theoretical significance and practical value.The main work of this paper described as followed:1. Under microwave irradiation, a series of 4-formyl pyrazole were obtained via the Vilsmeier-Haak reaction of acetophenone phenylhydrazone, which were synthesized using acetophenone derivatives and phenylhydrazine as raw material. 1,1’- ferrocene diethyl ketone was synthesized by the reaction of ferrocene and acetyl chloride using AlCl3 as catalysis, under microwave irradiation, it reacted with 4-formyl pyrazole in the NaOH solution to yield target compounds(3a-3d), and tetrabutyl ammonium bromide as catalysis. The yield is about 84%. Target compounds(3e-3h) were prepared under the same reaction conditions.2. 1, 1’-ferrocene oxalic acid was synthesized in 10% NaClO solution, 1,1’- ferrocene diethyl ketone as raw material. It reacted with methanol to yield 1,1’- ferrocene dimethyl formate with H2SO4 as catalysis. 1, 1’- ferrocene diformyl hydrazine was obtained by reaction of 1,1’- ferrocene dimethyl formate with 80% hydrazine hydrate. It reacted with 4-formyl pyrazole in the ethanol to yield target compounds(4a-4d) with ice acetic as catalysis. The yield is about 85%.3. Target compounds 5a-5d were synthesized by reaction of compounds(3a-3d) with thiosemicarbazide in ethanol solution under microwave irradiation, and NaOH as catalysis. The yield is about 83%. Target compounds(5e-5h) were prepared under the same reaction conditions. The structure of target compounds were confirmed by elemental analysis, 1H NMR, IR and MS.4. The ultraviolet spectrum test of target compounds showed that compound 3a-3h, compound 4a-4d and compound 5a-5h have absorption peaks in near 280 nm and 360 nm, but the absorption intensity of compounds is different. The fluorescence spectrum test of target compounds showed that compound 3a-3h have largest emission peak in the near 465 nm, compound 4a-4d have largest emission peak in around 380 nm, compound 5a-5h have largest emission peak in around 390 nm. The CV test of target compounds showed that compounds 3e-3h and compounds 5e-3h have ferrocene redox peak in the range of 0.5 ~ 0.8 v.