Polyarylacetylenes: Structure and properties

Abstract

Considerable confusion exists in the literature concerning the structure and properties of polyarylacetylenes. Taking into account the significant structural aspects from the literature data with our recent results on the polypentadeuterophenylacetylene isomers, we present our findings concerning this class of polymer.

Thermal, optical, electrochemical properties and conductivity of trans- and cis-poly(1-ethynylpyrene): a comparative investigation

“…In general, polyarylacetylenes exhibit trans-transoidal, cistransoidal, trans-cisoidal and cis-cisoidal geometries as shown in studies involving FTIR and 1 H NMR investigations of polyphenylacetylene [12,13].…”

Synthesis and Functionality of Substituted Polyacetylenes

“…The polyene backbone of a segment in a PA chain can adopt E-s-E, E-s-Z, Z-s-E, or Z-s-Z conformation [4,10,34]. Because the energy needed for the conformational conversion is small, the conformation of a PA segment is anticipated to be tunable by changing its surrounding environment.…”

“…Attachment of polar groups to the polyene backbone enables the integration of functional pendants into the PA chain through various functional-group transformations, which was, however, a difficult task at the early stage of PA chemistry. Difficulties were ascribed to the poisoning of the metathesis catalysts by the functional groups [10,11]. The later discovery of the functionality-tolerant organorhodium catalysts was a thrilling advance in the area [12,13], but the catalysts work for only limited types of monomers (e.g., phenylacetylene derivatives and monosubstituted 1-alkynes) through an insertion mechanism [14].…”

Molecular Shapes of Monosubstituted Polyacetylenes in their Liquid Crystalline Phases

“…This merit allows a full characterization of the main-chain conformation by various techniques. On the basis of 1 H NMR spectroscopy, Percec and coworkers developed a versatile method for the determination of the cis-content of poly(phenylacetylene) in the late 1970s, [30][31][32] which was later generalized for MSPAs containing functional side-chains. [5] In addition, 13 C NMR spectroscopy also helps to distinguish the stereoisomers.…”