Intramolecular thermal cyclization and benzannulation reactions of the Gould–Jacobs and Conrad–Limpach types were performed in a designed continuousflow reactor system at temperatures in the range of 300–360 °C and under high pressure conditions (100–160 bar) with very short residence times (0.45–4.5 min) in tetrahydrofuran as a low-boiling point solvent. Substituted heteroaromatic compounds including
Photoinduced Regioselective Chalcogenation and Thiocyanation of 4<i>H</i>‐Pyrido[1,2‐<i>a</i>] pyrimidin‐4‐ones Under Benign Conditions
作者:Abhinay S. Chillal、Rajesh T. Bhawale、Umesh A. Kshirsagar
DOI:10.1002/ejoc.202300665
日期:2023.9.6
A mild approach for regioselective C3−H chalcogenation and thiocyanation of 4H-pyrido[1,2-a] pyrimidin-4-ones is developed using visible light photo-catalysis. This operationally straightforward method furnishes a broad array of C-3, Ar−S/Ar−Se and -SCN functionalized derivatives in moderate to high yields using visible light as an environment friendly energy source.