Polyacetylenes from

GLASER - CHODKIEWCZ Acetylene Coupling Polyacetylenes from monoacetylenes in the presence of copper salts. 

Synthesis of polyacetylene from polyvinyl chloride by elimination of HC1. 

Figure 13 shows the irreversible conversion of a nonconjugated poly (p-phenylene pentadienylene) to a lithiun-doped conjugated derivative which has a semiconducting level of conductivity (0.1 to 1.0 S/cm) (29). Obviously, the neutral conjugated derivative of poly (p-phenylene pentadienylene) can then be reversibly generated from the n-type doped material by electrochemical undoping or by p-type compensation. A very similar synthetic method for the conversion of poly(acetylene-co-1,3-butadiene) to polyacetylene has been reported (30), Figure 14. This synthesis of polyacetylene from a nonconjugated precursor polymer containing isolated CH2 units in an otherwise conjugated chain is to be contrasted with the early approach of Marvel et al (6) in which an all-sp3 carbon chain was employed.

Synthesis of polyacetylene from poly(acetylene-co-1,3-butadiene). 

Identification of an Antibiotic Polyacetylene from Clitocybe diatreta as... 

Compounds. XVII. Four New Polyacetylenes from Garden Varieties of Coreopsis. Acta Chem. Scand. 8, 1741 (1954). 

Zidorn C, Johrer K, Ganzera M, Schubert B, Sigmund E M, Mader J, Greil R, Ellmerer E P and Stuppner H (2005), Polyacetylenes from the Apiaceae vegetables, carrot, celery, fennel, parsley, and parsnip and their cytotoxic activities , J Agric Food Chem, 53, 2518-2523. 

A chemical reaction occurs above 1.5 GPa The sample turns black, new peaks develop in the Raman spectrum, and the absorption edge moves below 11,000cm. The recovered material has an optical band gap of 1.39eV, smaller than the band gap of polyacetylene. From the analysis of the Raman spectrum, it is seen that the C=C stretching mode completely disappears in the reaction product, while the C=N stretching band is present but at a different frequency than in cyanocetylene. In addition, the Raman bands of polyacetylene are observed with their characteristic frequency dependence on the wavelength... 

The isomerization of polyacetylene from the cis- to the trans-form can be readily... 

Castiello, D., Cimino, G., De Rosa, S., De Stefano, S., and Sondo, G., High molecular weight polyacetylenes from the nudibranch Peltodoris atromaculata and the sponge Petrosia ficiformis, Tetrahedron Lett., 21, 5047, 1980. 

Norton, R.A., Finlayson, A.J. and Towers, G.H. (1985) Two dithiacyclohexadiene polyacetylenes from Chaenactis douglassi and Eriophyllum lanatum. Phytochemistry, 24 (4), 356-357. 

The above values were selected, in the case of polyacetylene, from averages taken from available experimental and theoretical structural data. For the halogenated chains, appropriate values were selected from the results of both ab initio and CNDO/2 molecular orbital calculations and from structural data available on small-molecule analogues. Due to the unavailability of structural data for the silylated analogues, values were taken from those used for polyacetylene (except, of course, for those bonds and angles associated with an X atom) so as to deduce the effect of the substitution alone without inclusion of concomitant structural modifications along the polymer backbone resulting from such substitutions. 

A graduate student in Hideki Shirakawa s laboratory at the Tokyo Institute of Technology was trying to make a polymer called polyacetylene from ordinary acetylene welding gas. The polymer, a dark powder, had first been synthesized in 1955, but no one knew much about it. Instead of a dark powder, Shirakawa s student produced a lustrous, silvery film that looked like aluminum foil but stretched like Saran wrap. Looking back over his chemical recipe, the student saw his... 

CH,=CHCH(OH)(C=C),-CH=CHCH(OH)(CH,)3CH,OH Scheme 4. Polyacetylenes from Campanulaceae species. 

Natural polyacetylenes part XLII, Novel C7, C3, Cg and Cio polyacetylenes from fungal cultures, M.T.W. Hearn Sir Ewart R.H. Jones, M.G. Pellatt,... 

Further polyacetylenes from Polyporus anthracophilus Specific incorporation of matricaria esters into polyacetylenic metabolites of this fungus, D.G. Davies, P. Hodge, P. Yates and M.J. Wright, J. Chem. Soc., Perkin Trans. 1, 1978, 1602. 

Bohlmann and his co-workers have described the synthesis of polyacetylenes from l-bromo-2-phenylacetylene and butadiyne in the presence of copper(i) chloride503 and by a multi-step method from bromopropiolic acid.504... 

Solid-State Production of Polyacetylene from Poly(dietbyl 7-oxabicyclo[2.2.1]hepta-2,5-diene-2,3-dicarboxylate)... 

Figure 5. The apparatus used in the chemical n-doping of polyacetylene from metal-... 

Gorman, C.B., Ginsburg, E.J., Grubbs, R.H., 1993. Soluble, highly conjugated derivatives of polyacetylene from the ring-opening metathesis polymerization of monosubstituted cyclooctatetraenes synthesis and the relationship between polymer structure and physical properties. I. Am. Chem. Soc. 115, 1397-1409. 

FIGURE 5.14. Energy variation and accompanying degree of lattice distortion to the displacement of a K ion (labeled K ) from its perfect-lattice site along the dopant axis in semidoped polyacetylene. (From Ref. 107 by permission of the publishers.)... 

FIGURE 15.48 Real and imaginary parts of the dielectric functions (solid lines) and loss function Imf-l/s) (dotted line) from Kramers-Kronig analyses of the reflectance spectra for light polarized parallel to the chain direction for highly oriented AsFs doped trans-polyacetylene. (From Leising, G., Phys. Rev. B, 38, 10313, 1988. Reprinted from the American Physical Society. With permission.)... 

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