Five kinds of polythiophenes bearing a crown ethereal subunit directly bonded to the thiophene ring have been prepared by the following organometallic polycondensation:,5-diyl with the crown ethereal subunit. Polythiophenes with alkoxy substituents (OCH3 and O(CH2)2OCH3) are also prepared by the organometallic polycondensation. The crown ethereal polymers exhibit photoluminescence in a range of 467-603 nm in both CHCl3 solutions and films. Their electroluminescence spectra essentially agree with the photoluminescence spectra. The crown ethereal polythiophenes have a high affinity toward Na + . After chemical oxidation (or p-doping) and reduction (or n-doping), the polymers show an electrical conductivity of 5.4 × 10 -7 to 1.8 S cm -1 . The Na-doped and electrically conducting state of crown ethereal polythiophenes shows some stability under air, which is attributed to the strong affinity of the polymer to Na + . Cyclic voltammetry of the crown and linear ethereal polythiophenes reveals a large difference (about 2 V) between n-doping and n-undoping potentials.
Ni-catalyzed dehalogenation polycondensation of 3-formyl-, 3-hydroxyiminomethyl-and 3-cyano-2,5-dibromothiophene with zinc affords oligo(3-formyl-2,5-thienylene) (Za), oligo-(3-hydroxyiminomethyl-2,5-thienylene) (2 b), and oligo(3-cyano-2,5-thienylene) (2c). Electrochemical polymerization of 3-methoxythiophene and 3,4-dimethoxythiophene give blueblack films of oligo(3-methoxy-2,5-thienylene) (2d) and poly(3,4-dimethoxy-2,5-thienylene) (2e).
Iodine adducts of2a -2c show electrical conductivity values between 1,8. lo-" and 8,8. lo-' S -c m -' . Doped 2d shows electrical conductivity of 2 . lo-' S . c m -' , whereas doped 2e exhibits an electrical conductivity between 1 3 and 30 S . cm-I . Doping of undoped 2 d and 2ecauses profound changes in their IR and NMR spectra, colour, and electrical conductivity properties.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.