Diketone-Based Boron/Platinum Compounds: Design,Synthesis,Photophysical Properties And Application

Beta-diketone contains tautomerization between keto form and enol form.Beta-diketone shows unique photophysical features and chemical features.The chemical strcuture of beta-diketone is easily modified.Beta-diketone is regarded as organic intermediates and chelating agents by chemists.Moreover,optical functional materials based on beta-diketone are a highly relevant topic owing to their applications in chemical sensing,flexible display,bio-imaging and so on.In this paper,we designed and synthesized a series of beta-diketone.We chose these beta-diketones as ligands to synthesize novel types of organic boron complexes and platinum complexes.They are regarded as optical functional materials.Their applications on polarity detection in cells and photodynamic therapy in tumer cells are researched.The main contents are as follows:Firstly,a series of ?-benzoylace-tophenone has been designed and synthesized.These beta-diketones containing aromatic groups are chromophoric moleculars with typical D-?-A-?-D structure.They hold two D-?-A charge transfer chains.Their photophysical properties are easily tuned.These beta-diketones have strong emission intensity.Organic boron complexes are excellent small molecular fluorescent materials which have advantages of mild synthetic conditions and tunable luminescence.By complexation with boron trifluoride ethyl ether,we acquired a kind of boron complexes based on diketone(O^O)BF2.Compared with ligand beta-diketone,boron complexes showed obvious red luminescence.Besides,boron complexes were sensitive to solvent polarity.With the increasing of polarity of the solvent,luminescence of boron complexes was gradually red-shifting.We used boron complexes as fluorescent probe in the detection of polar environment in homologous normal cells and cancer cells.Their photophysical properties changed.There exsisted 40 nm red-shift in Lambda spectrum.We found that boron complexes respond quickly to different polarity of cells.We can apply this property to polarity detection in different cells or organisms.Secondly,we chose 2-phenyl pyridine as main ligand and beta-diketone as ancillary ligand to synthesize platinum complexes Pt(ppy)(cpcpd).Cyclometalated platinum complexes have long luminescence lifetime,high quantum efficiency,significant Stokes shifts.They are outstanding organic phosphorescent materials.In addition,the platinum complex produced reactive oxygen species 1O2.Confocal imaging showed that platinum complexes based on beta-diketone could produce 1O2 and apoptosis tumer cells.Thus platinum complexes have great potential in photodynamic therapy for pathological tissue.