Efficient and selective syntheses of novel unsaturated chalcogen-containing pyridine derivatives

Natural Compounds and Their Structural Analogs in Regio- and Stereoselective Synthesis of New Families of Water-Soluble 2H,3H-[1,3]thia- and -Selenazolo[3,2-a]pyridin-4-ium Heterocycles by Annulation Reactions

“…The reactions of 2-pyridinesulfenyl chloride with isoeugenol leading to 3-(3,4-dimethoxyphenyl)-2-methyl-2Н,3Н-thiazolo[3,2-а]pyridin-4-ium chloride (1) in 70% yield was reported by us as a short letter [41]. In the present research, we increased the yield of compound 1 to 85% and proved that compound 1 has trans-configuration regarding the positions of The reactions of 2-pyridinesulfenyl and 2-pyridineselenenyl chlorides with some alkenes have been described [32][33][34][35][36][37][38][39][40][41]. The reactions of these reagents with styrene have been reported to afford 3-phenyl-2H,3H- [1,3]thiazolo-and -selenazolo[3,2-a]pyridin-4-ium chlorides in high yields [32,35].…”

“…]and [1,3] [32][33][34][35][36][37][38][39][40][41], reactions of 2-pyridinesulfenyl and 2-pyridineselenenyl halides with many alkenes are hitherto unknown. For example, the reactions of 2-pyridinesulfenyl and 2-pyridineselenenyl chlorides with simple 1-alkenes and natural compounds containing a double bond such as eugenol, isoeugenol, anethole and its derivatives have not been described.…”

“…2-Pyridinesulfenyl bromide and 2-pyridineselenenyl bromide were rarely used in organic synthesis and in the preparation of condensed heterocycles [37][38][39]. Usually organylsulfenyl and organylselenenyl bromides are less electrophilic than corresponding organylsulfenyl and organylselenenyl chlorides.…”

“…The development of effective approaches to novel selenium heterocycles by regioselective cyclization and annulation reactions is one of the main directions of our research [22][23][24][25][26][27][28][29][30][31]. The reactions of 2-pyridinesulfenyl and 2-pyridineselenenyl chlorides with some alkenes have been described [32][33][34][35][36][37][38][39][40][41]. The reactions of these reagents with styrene have been reported to afford 3-phenyl-2Н,3Н- [1,3]thiazolo-and -selenazolo[3,2-а]pyridin-4-ium chlorides in high yields [32,35].…”

“…The reactions of these reagents with styrene have been reported to afford 3-phenyl-2Н,3Н- [1,3]thiazolo-and -selenazolo[3,2-а]pyridin-4-ium chlorides in high yields [32,35]. In spite of some progress in synthetic method for preparations of [1,3]thiazolo[3,2-a]-and [1,3]selenazolo[3,2-a]pyridin-4-ium derivatives [32][33][34][35][36][37][38][39][40][41], reactions of 2-pyridinesulfenyl and 2-pyridineselenenyl halides with many alkenes are hitherto unknown. For example, the reactions of 2-pyridinesulfenyl and 2-pyridineselenenyl chlorides with simple 1-alkenes and natural compounds containing a double bond such as eugenol, isoeugenol, anethole and its derivatives have not been described.…”