Thianthrene-containing polyimides

M. Yoneyama, R. A. Johnson, and L. J. Mathias. Thianthrene-containing polyimides with monomer formation via nncleophiUc aromatic substitution. J. Polym. Set, Part A Polym. Chem., 33 1891-1899,1995. 

Overall goals of our research in this area include synthesis of thianthrene di-, tri- and tetracarboxylic acid derivatives (10,11,12,13 Figure 7) starting with 3,4-dichlorobenzoic acid and 4,5-dichlorophthalic acid evaluation of their use in formation of thianthrene-containing polyimides, aramids, and polybenzoxazoles and... 

Thianthrene-Containing Polymers Polyimides, Aramids, and Polybenzoxazoles... 

Thianthrene-di-, tri-, and tetracarboxylic acids, and a variety of their derivatives, were prepared and polymerized with co-monomers to obtain thianthiene-containing polyimides, aramids and polybenzoxazoles. The multiply substituted thianthrene derivatives were prepared starting with dichloro-substituted benzamide or phthalimide via chlorine displacement by sulfur nucleophiles. The protected carboxyl groups enhanced the displacement reaction to give thianthrene bisamides and imides in good yields. Deprotection with base gave carboxylic acid derivatives. 

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