- Phenylenevinylene oligomers by Mizoroki-Heck cross coupling reaction. Structural and optoelectronic characterization
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In order to study the effect of the molecular structure on the optical properties of totally trans-trans phenylenevinylene oligomers (OPVs), sixteen 1,4-distyrylbenzene derivatives (1a-i and 2a-g) functionalized with different electron-donating (ED) and electron-withdrawing (EW) groups were synthesized by the Mizoroki-Heck cross coupling reaction in moderate to good yields (40–95%). The implemented methodology, with a small modification previously reported by our group, allows obtaining the desired vinyl configuration as well as one novel OPV compound (1h). After structural characterization by several techniques (e.g. FTIR, 1H, 13C and Solid-State NMR), particular emphasis was placed upon the investigation of their optical properties by UV–vis and fluorescence spectroscopies. The results showed that, with only one exception, the ED and EW groups at the ends of OPV systems lead to a bathochromic shift. This effect is intensified with the introduction of methoxy groups on the central ring. Consistent with these, the HOMO-LUMO gaps (ΔE) decreases as the strength of ED and EW substituents increases. The ED and EW substituents also lead to a decrease in the Φf values. This contribution in the area of organic electronics can be used as a reference to better select the most appropriate technological application for each OPV and this can be extrapolated to their respective structurally analogous segmented polymer.
- Estrada, Sandra E.,Ochoa-Puentes, Cristian,Sierra, Cesar A.
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p. 448 - 457
(2016/12/30)
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- One-pot synthesis and study of spectroscopic properties of oligo(phenylenevinylene)s
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Two series of OPVs (oligo(phenylenevinylene)), that is, ((1E,1′E)-(2,5-dimethoxy-1,4-phenylene)bis(ethene-2,1-diyl))dibenzene derivatives and 4-((E)-4-((E)-styryl)styryl)pyridine derivatives with different functional groups of varying electronic properties have been synthesized by one-pot Wittig-Heck methodology. The synthesized derivatives have been studied for their optical properties. Amongst them the ((1E,1′E)-(2,5-dimethoxy-1,4-phenylene)bis(ethene-2,1-diyl))dibenzene derivatives with appropriate changes in the end group showed a significant impact on the UV absorption and emission spectra. Particularly NO2-OPV showed distinct solvatochromism in the wavelength range of 218 nm in different solvents. Whereas 4-((E)-4-((E)-styryl)styryl)pyridine derivatives showed clear acidochromism which can be detected visually as well as spectroscopically.
- Patel, Krupa N.,Bedekar, Ashutosh V.
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p. 6617 - 6621
(2015/11/09)
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- Solid state behaviour of vinyl quinones
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2,5-Bisvinyl-1,4-benzoquinones 1 and 2-vinyl-1,4-benzoquinones 2 substituted with aryl or ester end groups have been synthesized. The 2,5-bisstyryl-1,4-benzoquinones 1 (R=phenyl, p-tolyl, o-tolyl) crystallize with a 7 angstrom-stacking axis. But only for the o-tolyl derivative the contacts between the vinyl groups are close enough to allow a four-center type photopolymerization. The ester derivative 1 (R=COOEt) has a layer structure and can be photooligomerized in the crystal. The generated cyclobutane subgroups have twofold symmetry. The vinylquinones 2 (R=aryl) may be dimerized photochemically in the crystal at the vinyl groups to centrosymmetric cyclobutanes. Crystals with 4 angstrom stacking axis are also photoreactive.
- Irngartinger,Lichtenthaeler,Herpich,Stadler
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p. 349 - 360
(2007/10/03)
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- Syntheses and Crystal Structures of 2,5-Bis(2-arylvinyl)-1,4-benzoquinones and their Photochemical Reactivity in the Crystalline State
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The 2,5-bis(2-arylvinyl)-1,4-benzoquinones 1a-1e are formed from hydrolysis of their corresponding ketals 5 which are generated by anodic oxidation of the corresponding 1,4-dimethoxybenzene derivatives 4.The crystal structures of the quinone compounds 1a,
- Irngartinger, Hermann,Lichtenthaeler, Jochen,Fenske, Dieter,Baum, Gerhard
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p. 1411 - 1418
(2007/10/02)
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