1192029-63-2Relevant academic research and scientific papers
1,2,3-Thiadiazoles with unsaturated side chains; synthesis, polymerization, and photocrosslinking
Al-Smadi, Mousa,Hanold, Norbert,Kalbitz, Helga,Meier, Herbert
, p. 2539 - 2546 (2009)
1,2,3-Thiadiazoles with polymerizable functionalities in the 4-position were synthesized as potential negative photoresists. The polymerization to soluble, film-forming materials must leave the heterocyclic rings intact, because they are needed for photocrosslinking reactions to give insoluble materials. 1,2,3-Thiadiazoles 1 cycloeliminate N2 on irradiation. The resulting 1,3-diradicals 2 have various options for stabilization processes leading to alkynes 3 or to higher heterocycles 5-12. The generation of atomic sulfur and its involvement in these subsequent reactions must be avoided. Therefore, systems like model compound 1a, in which the 1,3-diradicals form 2-methylene-1,3-dithioles (dithiafulvenes) 9 were selected here. Optimization gave ultimately two materials for application as photoresists. Monomer 1c could be polymerized in the presence of boron trifluoride to soluble 1c′, which on irradiation formed 1c″ as a cross-linked insoluble polymer. Furthermore, thiadiazole 1f was attached to polystyrene 26. The resulting soluble polymer 1i′ yielded the insoluble material 1i″ on irradiation. Georg Thieme Verlag Stuttgart.
