Rigid Rod Conjugated Polymers for Nonlinear Optics. 3. Intramolecular H Bond Effects on Poly(phenyleneethynylene) Chains was written by Moroni, M.;Le Moigne, J.;Pham, T. A.;Bigot, J.-Y.. And the article was included in Macromolecules in 1997.Recommanded Product: 2-Amino-5-bromo-4-fluorobenzoic acid This article mentions the following:
The synthesis and the X-ray and optical characterization of conjugated soluble poly(phenyleneethynylene)s, in which the planarity of the backbone has been improved by intramol. H bonds, are described. The solubility of the polymers was enhanced by increasing the number of alkyl chains on the aryl group. The electron d. on the Ph ring was also modified by the amino and ester groups, introducing electron-donor or electron-acceptor groups, which also increase the polarizability. The polymers have been synthesized by polycondensation using a palladium-catalyzed coupling reaction, between a bromoaryl and an ethynylaryl unit, with HBr elimination. This method allows the insertion of a triple bond between two Ph groups. It was initially used to obtain oligomers or high mol. weight polymers, having important nonlinear susceptibilities. The new polymers have been characterized by UV-visible and Raman spectroscopies, as well as nonlinear optical measurements of the third-order susceptibilities (χ(3)). These measurements show the influence of the H bonds between the aryl groups on the absorption wavelength. In addition, the nonlinear optical measurements show that the χ(3) value of the pPY (6.8 × 10-10 esu) is close to the highest values obtained in acetylenic polymers such as polydiacetylenes. In the experiment, the researchers used many compounds, for example, 2-Amino-5-bromo-4-fluorobenzoic acid (cas: 143945-65-7Recommanded Product: 2-Amino-5-bromo-4-fluorobenzoic acid).
2-Amino-5-bromo-4-fluorobenzoic acid (cas: 143945-65-7) belongs to organobromine compounds. Bromine is more electronegative than carbon (2.9 vs 2.5). Consequently, the carbon in a carbon–bromine bond is electrophilic, i.e. alkyl bromides are alkylating agents. Commercially available organobromine pharmaceuticals include the vasodilator nicergoline, the sedative brotizolam, the anticancer agent pipobroman, and the antiseptic merbromin. Recommanded Product: 2-Amino-5-bromo-4-fluorobenzoic acid
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary