Thiocarbonylation of C(sp^(3))-H bonds in pyridylamines with CS;: Facile synthesis of pyrido[1,2-a]pyrimidine-4-thiones

Herein, a facile synthesis of valuable pyrido[1,2-a]pyrimidine-4-thiones is reported via novel thiocarbonylation of C(sp^(3))-H bonds with carbon disulfide(CS_(2)). This reaction features easy availability of substrates,good functional group tolerance, high yields, facile scalability and atom economy. Mechanistic investigations indicate that sulfate anion and sulfuric anhydride anion might be involved in this reaction.