Terthiophene derivative

Thiophene, 2,2-bithiophene, and 2,2, 5, 2"-terthiophene derivatives from Chinese medicinal plants as oncogene signal transduction inhibitors (proteinki-nase C inhibitors) 99PAC1101. 

Oligomers with 11 thiophene units showed an absorption maximum at 462 nm (91JA5887). The terthiophene derivative 21 and some other oli-gothiophene derivatives were studied because the coexistence of an electron-rich moiety (the terthiophene spine) and electron-deficient moiety (the dicyanomethylene groups on either side of the molecule) is expected to cause intramolecular charge-transfer (89BCJ1539 95BCJ2363 ... 

Due to the high degree of conjugation, oh go(thiophene)s advanced as attractive candidates for molecular bridges. For instance, Sato et al. [34] constructed hexyl-sexithiophene and methoxy-terthiophene derivatives bearing two terminal ferrocenyl groups. These served as model compounds for molecular wires. In the hexyl-sexithiophene derivative, the resultant oxidized states spread over both the ferrocene and the sexithiophene moieties. Similarly, in the methoxy-terthiophene derivative, the oxidized species spreads over the entire molecule containing the terthiophene and the other ferrocene moiety. In both cases, CT between the terminal units is inferred as it is mediated via the oh go(thiophene)s. 

Poly(3,3 -dialkyl-2,2 5 2-terthiophene) derivatives, (11), prepared by McCulloch [3] were also effective in electronic components as charge transport materials and semiconducters. 

Interest in photochromic systems other than those based on the hexa-fluorocyclopentene moiety continues to grow. The photochemical reactivity of the two photoswitches (35) is similar, and irradiation is efficient with conversions of 85% and quantum yields of around 0.6. The novel photo-chromic systems (36) undergo reversible ring closure in a reaction analogous to that observed in the bisthienyl system. Qin et al. have studied the novel pyridyl substituted cyclopentene system (37). This undergoes photocyclization with an enhanced quantum yield when the reactions are carried out in the presence of a metal. The pyridine units are capable of co-ordinating with the metal. The photochromic dithienylethene unit tethered to 3-cyclodextrin (38) has been used as a photoswitch to control the uptake of porphyrin. A series of new photochromic molecules (39) have been synthesized and studied. These exhibit the usual cyclization on irradiation. " The terthiophene derivatives (40) exhibit reversible photochemical cyclization (at 313 nm) and reversion (at wavelengths >460 nm) reactions. The cycles can be carried out many times... 

Recently, two other Ceo containing polymers have been synthesized by electropolymerization of terthiophene derivatives 241 and 242, respectively, by Komatsu [434] and Wudl [435]. The efficient photoelectrochemical response observed for poly(241) and the low bandgap in the order of 0.7 eV for poly(242) suggest that these compounds could be useful for the realization of solar cells. 

Less effort was spent recently on perfecting the conditions of electrodeposition in conventional or related conditions, except when a subsequent application was aimed at, which is indicative of, either a rising lack of interest in electropolymerization conditions, or that this technique has reached its limits. However, De Paoli et al. have recently investigated the optimization of the deposition conditions of a terthiophene derivative on indium tin oxide (ITO), with the further purpose to make a LED device [58]. 

Non-metalated terthiophene derivative 2.152 (17 %) was prepared by the condensation of bispyrryl-methane with 3 -formylterthiophene in trifluoroacetic acid, whereas the quinquethiophene derivative 2.153 was prepared by condensation of bispyrrylmethane and 3"-formylquinquethiophene with a Lewis acid as catalyst (Chart 1.31). NMR analysis of the free-base porphyrins 2.152 and 2.153 indicated an inseparable statistical mixture of PP- and a -conformations. Terthiophene-Zn(II)porphyrin 2.154 was prepared... 

Using tetraphenylmethane as a core, Liu et al. prepared tetrahedral branched bi- and terthiophene derivatives 5.47 n = 2, 3) and 5.48 (n = 2, 3) by Pd°-catalyzed aryl-aryl coupling methods (Scheme 1.65) [492]. The linkage of poly(ethylene glycol) (PEG) units to the fluorescent oligothiophene arms in 5.48 increased the water solubility of the tetrahedral chromophores. At the same time, in comparison with their parent... 

R. Michalitsch, A. El Kassmi, A. Yassar, P. Lang and F. Gamier, Increase of conjngation length within SAMs of terthiophene-derivatives, through electrochemical intermolecular coupling, J. Electroanal. Chem., 457, 129-139 (1998). 

M. Funahashi and J.-I. Hanna, High ambipolar carrier mobility in self-organizing terthiophene derivative, Appl. Phys. Lett., 76, 2574-2576 (2000). 

Table 4.9 Molecular structure and redox peak potentials of terthiophene, a quinoidal terthiophene derivative and the corresponding S,S-dioxides...

T. Kawai, T. Ikseda, M. Irie, Photochromism of triangle terthiophene derivatives as molecular re-router, Chem. Commun., 72-73 (2004). 

Badeva D, Tran-Van F, Beouch L, Chevrot C, Markova I, Racheva T, Froyer G (2012) Embedding and electropolymerization of terthiophene derivatives in porous n-type silicon. Mater Chem Phys 133 592... 

Aside from the arene-coupling methods, oligothiophenes can also be synthesized by ring closure reactions from aQ clic precursor molecules. Since there have been many reports using ring closure methods for the synthesis of mainly bi- and terthiophene derivatives [37], in the following only those examples which are related to conjugated materials are described. 

We now illustrate the impact of cyano functionalization on the electronic properties of oligo thiophenes. This issue is of prime interest in the context of organic light-emitting diodes, as demonstrated before in the case of PPV [72-74] the goal is to uncover the substitution patterns that lead to devices with enhanced efficiencies. In the following, we focus on cyano-substituted bi- and terthiophene derivatives that have been synthesized and characterized both electrochemically and optically by the Thiais group, see Fig. 6 [75]. 

Fig. 11.5 Typical film texture of polycrystalline thin films of a liquid crystalline terthiophene derivative, 8-TTP-8, observed by polarized optical microscope, atomic force microscope, and confocal laser microscope...

For a given class of liquid crystals having the same molecular core, the mobility is enhanced in a step-wise manner from phase to phase according to the increase in the molecular order in the mesophase. For smectic mesophases, the mobility is enhaneed according to the level of the molecular order within the smectic layer as follows, SmA, SmC < SmBhex SmF < SmBcryst. SmE, SmG. The mobility hardly depends on the orientation of molecular axis, i.e., whether this is perpendicular or tilted relative to the molecular layer. Figure 2.5 shows the mobility in various mesophases of 2-phenylnaphthalene and terthiophene derivatives as a function of the shortest intermolecular distance in each mesophase. It indicates clearly, that the... 

Fig. 2.6 Charge carrier mobility as a ftmction of temperature in various smectic mesophases of typical smectic liquid crystals 2-phenylnaphthalene and terthiophene derivatives...

Fig. 2.8 Charge carrier mobility as a function of temperature and electric field in a smectic mesophase of the terthiophene derivative, 5-hexyl-5"-hexynyl-2,2 5 2"-tetthiophene, which has a wide temperature range for a smectic mesophase...

Funahashi, M., Hanna, 1. Mesomorphic behaviors and charge carrier transport in terthiophene derivatives. Mol. Cryst. Liq. Cryst. 410, 529-540 (2004)... 

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