Synthesis of hydroxy-thiazoline substituted pyridine derivatives via [3+2] annulation of 1,4-dithiane-2,5-diol with cyanopyridine

A series of hydroxy-thiazoline substituted pyridine compounds were synthesized via the annulation of 1,4-dithiane-2,5-diol with cyanopyridine catalyzed by organic bases. The yields could reach up to 95%. The reaction required no solvent, and the products were obtained from raw materials and catalysts simply by grinding the mixture at room temperature for 10 min. The reaction could be well tolerated by variously substituted cyanide compounds. The universal applicability of this method was proven by gram-scale reaction and product derivatization.