ChemInform Abstract: 1,1′‐Sulfinyldipyridinium Bis (Hydrogen Sulfate) Ionic Liquid: Synthesis and Application in the Temperature‐Influenced Synthesis of Novel Pyranopyrimidinediones and Pyranopyrimidinetriones.

Abstract

1,1'-Sulfinyldipyridinium Bis (Hydrogen Sulfate) Ionic Liquid: Synthesis and Application in the Temperature-Influenced Synthesis of Novel Pyranopyrimidinediones and Pyranopyrimidinetriones. -At ambient temperature the reaction between 6-amino uracil (I) and salicylaldehydes in ethanol provides pyranopyrimidinediones [cf. (III), (VI), (VIII)]. In refluxing ethanol (I) and salicylaldehydes containing electron-withdrawing groups form pyranopyrimidinediones as well [cf. (IIId)], whereas salicylaldehydes equipped with no or electron-donating substituents react to the corresponding novel pyranopyrimidinetriones [cf. (IV)]. The catalyst is recovered and reused in four additional cycles with slightly decreasing reaction yields. -(PATIL, J. D.; KORADE, S. N.; PORE*, D. M.; RSC Adv. 4 (2014) 92, 50449-50455, http://dx.