Oxacalixarene Cages:Synthesis,Derivatization And Performance

Porous materials play an important role in the fields of gas adsorption and storage,catalysis and new energy materials,and are expected to provide new ideas for solving the two major problems that are environmental pollution and energy shortage.In recent years,metal organic frameworks?MOFs?and covalent organic frameworks?COFs?have attracted much attention due to their tunable pore size.However,to some extent,the practical application of these frameworks is limited because of the complexity of synthesis,stabilitiy and insolubility in any oraganic which make it unprocessable.Cages,prossessing tunable internal cavity,various synthesis methods and good solubility,can expand the application field of porous materials.In this thesis,several novel aromatic calixarene cage were constructed by nucleophilic aromatic substitution reaction?S_NAr?,and their porous capacity and application in florescence sensor and biological imaging were studied.1.Three triphenyl-benzene-based and triphenyl-triazine-based bioxacalixarene cages 2-6,2-7 and 2-8 were abtained by S_NAr reactions.In the solid state,cage 2-6 can be assembled into interlaced porous networks and achieve highly selective adsorption of CO₂/N₂=106 at 273 K.While,cage 2-7 and 2-8 assembled into nonporous frameworks.cages 2-7 and 2-8,as monomers,can be constructed into porous organic polymers?POPs?2-9 and 2-10 through Yamamoto-type Ullmann crosslinking reaction.The formed compounds 2-9 and 2-8 can“open”the internal cavities of POPs 2-7 and 2-8 and formed external connective tunnel,which exhibit good enhancement in pore performance.Furthermore,the CO₂ adsorption capacity and the selectivity of CO₂/N₂ can be enhanced by introducing N atoms into frameworks of POPs.2.Utilizing the strategy of“cage to frameworks”,a new fluorescent networked cage3-4 was synthesized by using tetraphenylethylene?TPE?-based oxacalixarene cage 3-3 as monomer.The networked cage 3-4 features improved porous properties including BET surface area and CO₂ capture compared to cage 3-3 because the polymerization overcame the window-to-arene packing modes of cages and turned-on their pores.Moreover,compounds 3-4 displayed prominent reversible fluorescence enhancement in the presence of CO₂ in methanol system and fluorescence recovery for CO₂ release in the presence of NH₃·H₂O,and is thus very effective to detect and quantify the fractions of CO₂ in a gaseous mixtures.3.A tetraphenylethylene-based oxacalixarene macrocycle 4-3 with high fluorescence quantum yield?70%?was used as monomer to construct a fluorescent macrocycle-basd porous organic polymer 4-4.With high surface area,specific pore size and emissive properties,the blue-greenish fluorescent 4-4 can be developed into a white-light-emission materials by adsorbing guests of tris?bipyridine?ruthenium with complementary emission color by F?rster resonance energy transfer?FRET?effect.4.An emissive star-like cage-based organic temperature sensitive polymers 5-7 was synthesized that can assemble into nanoparticles in aqueous solution.The obtained nanoparticle 5-7 can be easily tuned to full-color emission?including white light emission hybrid nanoparticles WNPs?by encapsulating different doses of guest dyes?compoumd5-8 and Nile Red?NR??through cascade F?rster resonance energy transfer?FRET?effect.Moreover,the WNPs exhibit reversible stimuli-response toward temperature with a temperature resolution of at least 0.5°C,and can be used as probes for temperature sensing in live cells through their fluorescent color variation between white and orange emission with good cytocompatibility.