Synthesis And Properties Of Reactive-based Probe On The Basis Of Fulvene Structure

The multi-substituted fulvene structure is a very important framework structure in organic synthesis and some functional molecules.Scientists show great interest in modifying the structure of the fulvene molecules and exploring their properties and the reactivities.In this dissertation,chlorine-substituted fulvene was synthesized under the presence of POCl₃ and DMF,and then the reaction of chlorofulvene with amine nucleophiles was discussed.The experimental data show that chlorofulvene can undergo nucleophilic substitution reaction with primary amines and secondary amines at room temperature rapidly and selectively.Comparing the UV absorption spectra between chlorofulvenes and nucleophilic substitution products,we found that the maximum absorption wavelength of the product shifted to the long-wave direction.Therefore,based on the above characteristics of the reaction,chlorofulvene can be used as a reaction-based probe for the detection of primary and secondary amine molecules,the main contents involve:1)Firstly,the polysubstituted 6-hydroxyfulvene was used as raw material to synthesize chlorine-substituted fulvene under the condition of DMF and POCl₃,using acetonitrile as solvent,and afforded a good yield（up to 86%）.2)Then the reactions of chlorine-substituted fulvene and amines were studied.We found that chlorine-substituted compound could react not only with primary amines but also secondary amines in a pretty good yield（up to 91%）.Inspiringly,chlorine-substituted fulvene can just react with amines selectively,even in the presence of some oxygen or sulfur containing nucleophiles.Moreover,we found a significant change in their UV absorption spectra between chlorine-substituted fulvene and their substitution products which can be applied to detect of primary and secondary amines.3)Finally,we studied the effect of concentration of amines on this substitution reaction by using chlorine-substituted fulvene as a reaction-based probe.According to the UV absorption spectra of products,we found the absorbance of the product is linearly related to the concentration of amines and the correlation coefficient was more than 0.99,the detection limit was 1×10^-6 mol/L for each different amines.