Synthesis And Test Of Rhodamine And Diarylethenes Functional Molecular

Synthesis, measurements, and applications of rhodamine and diarylethenes functional molecules wereinvestigated in detail.Rhodamine is an excellent fluorescent framework and has a unique sprio-lactam structure. It can leadto "on" and "off" changes of the ring through the external induction. The fluorescence and color changescan be observed by naked eye or detected by instrument. Functional group （electron-donor orelectron-acceptor） are incorporated the framework of rhodamine, which have been widely used forconstructing functional molecules. In this dissertation, functional molecules with aldehyde condensed withthe hydrazine or ethylenediamine groups of rhodamine. The method is very simple and efficient. A series ofrhodamine B derivatives are synthesized and characterized.1. It proves that compound a is highly selective and sensitive to identification of Zn²⁺and Cu²⁺by thecolor change and fluorescence quenching and can be used as ratiometric detection Zn²⁺and Cu²⁺accordingto job curve and magnetic resonance. The way of complexation can be confirmed by way of proton NMRtitration experiments. The multi-signal input and output can also be applied to the logic gate system.2. It also proves that compound c has a good selectivity for identification of Zn²⁺and Cu²⁺throughvarious means of detection, and can be used to ratiometric detection these two ions by job curve. Thecompound c serves as an excellent colorimetric chemosensor.The cyclization reaction of diarylethenes photochromic compounds has good fatigue resistance andthermal stability, and the optical isomers can lead to the change of the alternation of physical properties.These compounds have unique photochemical properties and potential applications in data storage, drugrelease, and bio-image. A series of novel diarylethene with thiophene/thiazolidinediones vinylphotochromic compounds were synthesized by conventional Stille coupling reaction.1. Compound o is an unsymmetrical photochromic triangle thiophene molecule. It combined theadvantages of compounds o and4.23which are symmetrical photochromic molecules. Although themolecule is small, it is thermal stability and fatigue resistance even if multi-cycle cyclization andcycloreversion without obviously degradation according to the absorption spectrum. It is believed that thecompound o can be served as an excellent switching molecule, which can be further functionalized at α-position. Our work along this line is in progress.2. Benzothiophene/thiazole with photochromic hexatriene framework are designed and synthesized.Excited by254nm, obviously color change is observed. They can convert alternately between the open andclosed-ring in solution state. New-type molecular switch system are constructed.