Conjugated polymers substitutes

Dobrosavljevic V, Stratt R (1987) Role of conformational disorder in the electronic-structure of conjugated polymers substituted polydiacetylenes. Phys Rev B 35 2781-2794... 

Conjugated polymers substituted by optically active groups, potentially useful as materials for enantiose-lective modified electrodes, have been prepared [174]. Some polymers have been synthesized by electropolymerization of enantiomeric monomers [175]. The polymers exhibited high stability and conductivity. The specific rotations are anomalously high, which has been interpreted by a macromolecular asymmetry arising from an helical polymer structure [176]. Electropolymerization of (S)-( -I- )-3-(2-methylbutyl)-thiophene provided another example of chiral polythiophene [177]. 

The versatility of poly(phenylcne) chemistry can also be seen in that it constitutes a platform for the design of other conjugated polymers with aromatic building blocks. Thus, one can proceed from 1,4- to 1,3-, and 1,2-phenylene compounds, and the benzene block can also be replaced by other aromatic cores such as naphthalene or anthracene, helerocyclcs such as thiophene or pyridine as well as by their substituted or bridged derivatives. Conceptually, poly(pheny ene)s can also be regarded as the parent structure of a series of related polymers which arc obtained not by linking the phenylene units directly, but by incorporation of other conjugated, e.g. olefinic or acetylenic, moieties. 

Figure 9-1. Materials overview a few sclcclcd conjugated polymers and Ihcir properties have been compiled and ihe following abbreviations arc used DO-PPP...Poly(2-decyloxy-l,4-phcnylcnc), EHO-PPP...Poly(2-(2 -elhylliexyloxy)-l,4-phcnylenc), CN-PPP... Poly(2-(6 -cyano-6 -incthyl-licplyloxy)-l,4-phcnylene), m-LPPP... methyl-substituted ladder-type Poly( 1,4-phenylcne), and PLQY=phololuinincs-ecncc quanluni yield.

Additional chemical stability can be given to PPVs by substitution at the vinyl-ene carbons. Thus, CN-PPV and PPV-DP are more stable than their parent polymers [173]. Carter et al. [172] showed that a random copolymer of PPV containing non-conjugated segments is considerably more stable to photooxidation than the fully conjugated polymer. Of course, the electrical and optical properties are also altered by these substitutions. 

A comparison of the absorption and emission spectra of Ooct-OPV5 with those of the fully conjugated, similarly substituted polymer Ooct-PPV shows that the absorption and luminescence maxima of the five-ring model compound are only slightly blue-shifted relative to those of the polymer (see Fig. 16-11). Hence, the... 

The sulfonium precursor route may also be applied to alkoxy-substituted PPVs, but a dehydrohalogenation-condensation polymerization route, pioneered by Gilch, is favored 37]. The polymerization again proceeds via a quinomethide intermediate, but die syndicsis of the conjugated polymer requires only two steps and proceeds often in improved yields. The synthesis of the much-studied poly 2-methoxy-5-(2-ethylhexyloxy)-l,4-phenylene vinylene], MEH-PPV 15 is outlined in Scheme 1-5 33, 35]. The solubility of MEH-PPV is believed to be enhanced by the branched nature of its side-chain. 

Several other organoboron polymers have been developed by various synthetic strategies and utilized to construct polymeric sensing systems for cations, dopamine, saccharides, and so on. Fabre and co-workers have reported the preparation of a conjugated trifluoroborate-substituted polythiophene system for sensing cations such as... 

Poly(iV-substituted dithieno[3,2-3 2, 3 -rf pyrroles (PDTPs) 167a,b) <2005MM4545>, a class of soluble (chiral) conjugated polymers with a stable oxidized state, were prepared by an oxidative coupling by FeClj in chloroform under an argon atmosphere. The crude material was reduced with hydrazine to afford compound 167 (Scheme 19) <2005MM4545>. 

A route to processible polyacetylene, devised initially using classical initiators (Scheme 1i) 576-578 has been developed using well-defined molybdenum initiators to prepare conjugated polymers.579-585 They have also been employed to prepare polyacetylene via the polymerization of cyclooctate-traene, COT,586 and by the isomerization of poly(benzvalene).587 588 Substituted, and hence soluble, polyacetylene derivatives may be synthesized by polymerizing monosubstituted COT substrates.589-591... 

Add CDI-mPEG to this solution with stirring to bring the final concentration of the activated polymer to 180 mM. Note Other ratios of polymer-to-protein may be used, depending on the modification level desired. Some optimization of the derivatization level may have to be done to obtain conjugates having the best amount of polymer substitution with retention of protein activity. 

B. Jiang, S.-W. Yang, R. Niver, and W.E. Jones, Jr., Metalloporphyrin polymers bridged with conjugated cyano-substituted stilbene units, Synth. Met., 94 205-210, 1998. 

L. Ding, D.A.M. Egbe, and F.E. Karasz, Photophysical and optoelectronic properties of green-emitting alkoxy-substituted PE/PV hybrid conjugated polymers, Macromolecules, 37 6124-6131,2004. 

Lavigne JJ, Broughton DL, Wilson JN, Erdogan B, Bunz UHF (2003) Surfactochromic conjugated polymers surfactant effects on sugar-substituted PPEs. Macromolecules 36 7409-7412... 

Two other related routes to conjugated polymers are the base-catalysed condensation of methyl-substituted aldehydes ... 

C. 0-71 Conjugated Polymers with an Alternating Arrangement of a Disilanylene Unit and 3,4-Diethynylene-Substituted Siloles... 

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