Synthesis Of Thioether Derivatives With Molecular Recognition

Calixarene possesses synthetic versatility and is easy to be functionalized. besides to functionalization at the para position of the aromatic rings (the upper rim) and the phenolic hydroxyls (the lower rim), it can also be modified at the bridging methylenes, aromatic walls and meta positions. As a result, various functional groups can be introduced to the parent compound. Calixarene has a cavity composed of benzene rings which behave likeπ-donors and can coordinate with appropriate molecules. Besides, the functionalized groups introduced can generally increase the cavity size and provide additional complexation centers for guest ions. Their capability to engulf ions or neutral molecules, grant them wide range of applications in host-guest chemistry. Self-assembled monolayers (SAMs) have dense and stable structures, which has win comprehensive applications in building blocks for superlattices. Sulfur compounds, which have strong affinity to transition metal surfaces because of the possibility to form multiple bonds with surface metal clusters, can easily form monolayer on gold surface and are most frequently used in SAMs.Based on calixarene's molecular recognition and sulfur compounds'wide range of application in SAMs, we have combined calixarenes and organosulfur compouds together in this paper. The obtained compounds are expected to form SAMs on gold nanoparticles and be applied molecular recognition.The first chapter is the background of this research. Calixarene and SAMs are briefly introduced, after which previous work in my laboratory is illustrated. Then main work of this paper is discussed based on previous achievements of my laboratory.In the second chapter, synthesis of calix[4]arene and precursor calixarene derivatives are introduced. Reported one-step synthesis of calixarene is explored and the conditions are improved to synthesize tert-butyl calix [4] arene at high yield. Based on references, appropriate conditions are selected to protect phenolic hydroxyl at the lower edge of the calixarene through Williamson reaction. After then, thio acid base are introduced through nucleophilic substitution reaction of alkyl halides.In the third chapter, on the basis of the precursor derivatives synthesized in chapter two, sulfide and disulfide calixarene derivatives are synthesized through different ways and sulfur functional group are successfully introduced into the calixarene molecules. In addition, two calixarene derivatives containing thiol groups are also designed and synthesized in this chapter. Their synthetic method and reaction process are deeply studied, which provides a good reference value for future synthesis of these compounds.Currently, these target compounds are waiting for self-assembly testing on nano-gold particles and are expected to perform good assembly results.The structure of some intermediates and all target compounds synthesized in this paper were confirmed by1H NMR,13C NMR, IR and MS.