Pyrolysis sulfonium salt

With electron-rich aromatic systems (such as dial-koxy-substituted phenylene or thiophene) this hydrolysis reaction is complete within a matter of hours at room temperature. The presence of these hydroxy or methoxy groups complicates the subsequent pyrolysis step and can lead to residual unsaturation in the main chain. It is also possible to get some substitution of the sulfonium salt with the counterion, although this reaction may be more prevalent in the solid state [47] or at elevated temperatures in solution [93]. The chloride and bromide precursor polymers are not stable in the solid state at room temperature, quickly turning yellow and becoming insoluble due to partial elimination. However, they can be... 

Y. Sonada and K. Kaeriyama. Preparation of poly(2,5-diheptyl-l. 4-phenylenevinylene) by sulfonium salt pyrolysis. Bull. Chem. Soc. Jpn. 65 853 (1992). 

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