Synthesis And Properties Of Diarylethenes Based On Naphthalimide And Aryl Rings

Among all the photochromic compounds, diarylethene compounds become most extensively studied one photo-chromic material due to their excellent thermal stability, significant fatigue resistance and light sensitivity. They can be potentially applied in optical memory, logic circuits, and chemical sensors. Currently, the strategy for fluorescence modulation what is to combine the diarylethene unit with a fluorophore, and the fluorescence of fluorophore can be controlled by external stimuli has gained a lot of interest. Ten kinds of diarylethenes molecule and two kinds of symmetric dimer diarylethenes molecule were synthesized based on the above ideas. Their photochemical properties was investigated systematically, the main contents are as follows:In chapter 1, the research background, application in chemical and biological fields of diarylethene compounds were reviewed. Their application in fluorescent switch and ion recognition were intensively introduced. Based on on the survery of the current focus our research subject was brought out.In chapter 2, two novel diarylethene with a di-(ethyl-1,8-naphthalimidyl)amine unit were synthesized, and the multi-responsive photoswitching property of DTE-1-2 induced by light, proton, and ions was investigated. The emission intensity of diarylethene DTE-1 could be independently modulated by UV-vis light and TFA/TEA. DTE-1 could be a promising candidate for the construction of a reversible and multi-state fluorescence switch. Upon addition of Sn2+, the fluorescence intensity of diarylethene DTE-1 was enhanced obviously. This title compound could serve as a fluorescence probe for the recognition of Sn2+.In chapter 3, two novel photochromic diarylethene dimers linked by a diphenylimine with ethyl-1,8-naphthalimides were synthesized. The photochromic reaction mechanism and their multiple fluorescence switch induced by sequential stimulations with protons, light and ions of DTE-3-4 were investigated. It is noteworthy that DTE-3 could construct a multiple switching system with reversible UV/vis irradiation, protonation/deprotonation and complexation/dissociation processes.In chapter 4, eight diarylethenes with a variable heteroaryl ring bearing various aromatic stabilization energies (ASE) have been synthesized. Experimental results showed that their thermal stability as well as cyclization quantum yield, cycloreversion quantum yield, photoconversion ratio, and fatigue resistance exhibited a strong correlation with ASE.