Carbon-Sulfur and Carbon-Selenium Double Bond Formation Through Thiolysis and Selenolysis of 4-Methylsulfanyl-Substituted Pyridinium and Quinolinium Halides

Abstract

4-Methylsulfanylpyridinium and -quinolinium salts 3 and 4 with alkyl groups such as methyl, allyl, benzyl, ethoxycarbonylmethyl, benzoylmethyl on the nitrogen atom were prepared by the Menschutkintype reaction and some of them caused to react under either the thiolysis or selenolysis reaction conditions. N-Substituted pyridine-4thiones 5a-c and quinoline-4-thiones 6a-e were formed at different rates in high isolated yield. On the other hand, two N-alkyl-4-selenopyridones 7a,b together with three 4-selenoquinolones 8a,b,c were also produced in high chemical purity and characterized spectroscopically. In addition, 4-sulfanylpyridone 12 and 4-selenopyridone 13 with a N-tert-butyl group were obtained via Zincke's salt 9. The overall process provides a useful alternative to the otherwise difficult direct N-alkylation of thioxo-and selenoxopyridine systems.

Turn‐on chemosensors for silver ions based on oligomers with diaza‐16‐crown 6‐ether receptors and aromatic fluorophore end groups

“…Compound 1 was prepared according to the literature 27–36. Other reagents were purchased and used without further purification.…”

“…It has been reported before that various pyridinium compounds can be synthesized by the reaction of 1 with primary amines 27–35. In the work reported in the present paper, this polymerization method was applied for the synthesis of the proposed oligomer: reactions of DA18C6 and 1 and subsequent end‐capping reactions with 2,5‐bis(aminophenyl)‐1,3,4‐oxadiazole ( 2 ) or 2,7‐diaminofluorene ( 3 ) were carried out to obtain oligomers with DA16C6 acceptors and 2,5‐diphenyl‐1,3,4‐oxadiazole or fluorene fluorophores.…”