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

Regio- and stereoselective syntheses of novel unsaturated chalcogen-containing pyridine derivatives [3-(vinylsulfanyl)- and 3-(vinylselany1)-2H,3H-[1,3]thiazolo[3,2-a]pyridin-4-ium chlorides, ethyl 3-(2-pyridinylsulfanyl)-2-propenoate, 1-phenyl-3-(2-pyridinylsulfany1)-2-propen-1-one, allenyl 2-pyridinyl telluride] have been developed using the previously unknown electrophilic and nucleophilic reactions of 2-pyridinylsulfanyl chloride and 2-pyridinechalcogenolate anions. (C) 2016 Elsevier Ltd. All rights reserved.