Synthesis And Characterization Of Compounds And Water-soluble Fluorescent Polymers Containing Fluorene Units

There is a growing interest in fluorescent conjugated polymers recently years.Conjugated polymers（CPs）contain a set of structural attributes that make them useful in optical and electronic detection of chemical and biomolecular fields,such as metal ions,fluoride,biomolecules,proteins and DNA as well.Real-time and reversible measurement of chemical and biological information with high sensitivity and selectivity is one of the frontiers in sensor researeh.In this thesis,we have synthesized three compounds containing fluorene unit and three water-soluble fluorescent polymers,and those properties and structures have been tested and characteiried.2,7-di[4-（acryloyloxy hexyloxy）phenyl]-9,9-di（n-octyl）fluorene（M2-C6）containing fluorene unit and acrylate group was synthesized using 2,7-dibromofluorene,1,6-dibromo hexane and 1-bromooctane as starting materials.S-1-dodecyl-S’-[poly（N-Boc-acryloyl ethylene diamine）-2’-methyl propionic acid]trithiocarbonate（P1）with trithioester as end group was prepared via reversible addition-fragmentation chain transfer（RAFT）polymerization.Boc-protected amino groups and regular structure fluorescent polymer containing fluorene unit（2,7-di{4’-[3’’-（S-poly（N-Boc-acryloyl ethylene diamine）-2’’’-methyl propionic acid）propionyloxy hexyloxy]phenyl}-9,9-di（n-octyl）fluorene（P2-C6））was prepared（in the same reaction bottle,both the reduction reaction of trithioester bond of P1 to sulfydryl and the in situ Click reaction of sulfydryl and the carbon-carbon double bond of M2-C6 were occured at the same time）.P2-C6 displayed good solubility in common organic solvents such as dichloromethane,trichloromethane and tetrahydrofuran.Water-soluble fluorescentpolymer（2,7-di{4’-[3’’-（S-poly（acryloylethylenediamine hydrochloride）-2’’’-methylpropionicacid）propionyloxyhexyloxy]phenyl}-9,9-di（n-octyl）fluorene（P3-C6））containing fluorene unit was obtained by the deprotection of the resulting Boc-protected polymer（P2-C6）with aqueous HCl.M2-C6,P1,P2-C6 and P3-C6 were characterized and measured by Fourier transform infrared spectroscopy,nuclear magnetic resonance spectrometer,high-resolution mass spectrometer,gel permeation chromatography,UV-Visible spectrophotometer and fluorescence spectrophotometer,respectively.These results showed that P2-C6 exhibited bright blue fluorescence emission in solution.After deprotection,P3-C6 displayed good solubility in water and not only exhibited blue fluorescence emission in water but also had the similar photoluminescent spectrum with those of M2-C6 and P2-C6 in dichloromethane.The fluorescence quantum yield of P3-C6 in aqueous solution could reach 0.10.The results revealed that cell viability could reach 80%even then the concentration of P36 was 15μg·m L^-1 and the incubation time was 24 h.This experiment provided a novel approach for preparation of regular structure water-solvent fluorescent polymer.M2-C2 and M2-C4 were synthesized by the same methods of M2-C6.Two kinds of fluorescent polymers（P2-C2 and P2-C4）containing fluorene units with different structures were prepared by one-pot method.Water-soluble fluorescent polymer P3-C2 and P3-C4containing flourene unit were obtained by the deprotection of the resulting Boc-protected polymer P2-C2 and P2-C4 with aqueous HCl,P3-C2 and P3-C4 were characterized and measured by many modern analytical instrumental methods.The optical properties of P3-C2,P3-C4 and P3-C6 were tested in different p H aqueous solutions.These results showed that P3-C2 and P3-C4 have been prepared successfully with good photoluminescence.The results were that the fluorescence intensity of P3-C2,P3-C4 and P3-C6 increased with the increasing of p H in water solutions.