Synthesis And Properties Of Oligo(Phenylene Vinylene)Derivatives

In this thesis,hydroquinone was utilized as an inexpensive and readily available starting material to afford several organic building blocks with different functional groups,such as aldehyde,cyano,and phosphonate,via a bottom-up organic synthetic strategy.Through Horner-Wadsworth-Emmons reaction or Knoevenagel condensation reaction,oligo(phenylene vinylene)derivatives 13,14,15,and 16 were successfully prepared with benzene ring containing OCsH17 alkoxy chain structure and different terminal groups(I or CF3).The structures of the above compounds were characterized by NMR and ESI-MS.Meanwhile,their optical properties were investigated by UV-vis and fluorescence spectroscopy.The specific content is as follows:1.Synthesis of compound 13Compound 13 was obtained by Knoevenagel condensation reaction of commercially available p-iodophcnylacctonitrilc and compound 12 in the presence of potassium tert-butanol as base(Scheme 1).Compound 13 was a new compound,which was characterized by NMR and ESI-MS.2.Synthesis of compound 14Compound 14 was obtained by Ilorncr-Wadsworth-Emmons reaction of compounds 6 and 11 in the presence of potassium tcrt-butanol in THF solvent(Scheme 2).Compound 14 was a new compound,which was characterized by NMR and ESI-MS.3.Synthesis of compound 15Compound 15 was obtained by Knoevenagel condensation reaction of compound 9 with compound 12 in the presence of potassium tert-butanol as base(Scheme 3).Compound 15 was a new compound,which was characterized by NMR and ESI-MS.4.Synthesis of compound 16Compound 16 was obtained by Knoevenagel condensation reaction of commercially available 3,5-bis(trifluoromethyl)phenylacetonitrile with compound 12 in the presence of potassium tert-butanol as base(Scheme 4).Compound 16 was a new compound,which was characterized by NMR and ESI-MS.5.Optical propertiesThe optical properties of compounds 13-16 were investigated by UV-vis and fluorescence spectroscopy.The data of UV-vis spectroscopy showed that:Compared with compound 14,the introduction of cyano groups in compound 15 made the absorption peak red-shift to longer wavelength.Compared with compound 13,the effect of the alkoxy chain in compound 15 did not cause a significant red-shift of the absorption peak.For compound 16 bearing both trifluoromethyl and cyano groups,a stronger absorption peak in the long wavelength was observed.Fluorescence spectra data show that compounds 13-16 have strong fluorescence emission characteristics around at 500 nm.