Pressure-Induced cis-to-trans Isomerization of Poly[(p-methylthiophenyl)acetylene] Prepared with a [Rh(norbornadiene)Cl]2 Catalyst – A Raman, UV-Vis, and ESR Study

✍ Scribed by Kai Huang; Yasuteru Mawatari; Masayoshi Tabata; Takeyuki Sone; Atsushi Miyasaka; Yoshikazu Sadahiro

• Book ID: 102486538
• Publisher: John Wiley and Sons
• Year: 2004
• Tongue: English
• Weight: 162 KB
• Volume: 205
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.200300065

✦ Synopsis

Abstract

Summary: A stereospecific polymerization of a novel aromatic acetylene containing an alkyl sulfide group, i.e., (p‐methylthiophenyl)acetylene (__p__MeSPA) was successfully performed to selectively give the corresponding polymer bearing a cis‐transoid structure as a main geometrical form and a very high molecular weight, $\overline M _{\rm n}$ = 1.7–5.8 × 10^6^ in high yields. This was accomplished when a Rh complex catalyst, [Rh(norbornadiene)Cl]~2~, was used in the presence of triethylamine (TEA) solvent as a cocatalyst and its mixed solvents with TEA, together with a detailed characterization of the resulting polymers before and after compression at room temperature. Based on the data obtained before and after compression, it was concluded that compression of the P__p__MeSPA polymers induced a cis‐to‐trans isomerization at room temperature under vacuum even in the solid state (the Figure shows the radical generated by compression).
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