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We herein report the preparation of a soluble polyimide from a photoreactive diamine and a phenolic diamine, to which electro-optic (EO) properties were imparted by the introduction of an EO chromophore (Disperse Red 1) into the phenolic group of the polyimide. Following poling at 1 MV/cm and 210 °C, the polyimide was irradiated with UV light (280–310 nm) to form a photo-crosslinking network. The EO coefficient of the polyimide-containing EO device was 27.7 p.m./V at 1.3 μm, and this value was maintained at ≥90%, even after annealing at 150 °C for 500 h. Our results indicated that the thermal and chemical stabilities of the EO polyamide were remarkably increased due to the photo-crosslinking reaction.

The highly selective anti-Markovnikov addition of thiols to unactivated alkenes and alkynes was demonstrated by using 3,4-dimethyl-5-vinylthiazolium iodide or its polymer, poly(3,4-dimethyl-5-vinylthiazolium) iodide, as a complementary catalyst. The reaction proceeded cleanly under base-free conditions in air with both aromatic and aliphatic thiols. The polymer catalyst showed a high turnover number (≈5800) and could be reused up to four times without any loss of catalytic activity. DFT calculations supported stabilization of the thiyl radical intermediate by the thiazolium cation, which resulted in reaction of the radical with unsaturated C−C bonds.

Poly(3,4-dimethyl-5-vinylthiazolium) was synthesized from 3,4-dimethyl-5-vinylthiazole through free radical polymerization and was examined as polymer precatalysts in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) for the thioesterification of aldehydes with thiols. The poly(5-vinylthiazolium)/DBU had excellent catalytic activity and could be reused 10 times without a considerable loss of activity.

The title catalytic system exhibits high catalytic activity for the thioesterification of aldehydes.