Efficient One‐Pot Synthesis of 2‐Oxo‐1,9a‐dihydro‐2H‐pyrido[1,2‐a]pyrimidine Derivatives.

Abstract

Fused pyrimidine derivativesFused pyrimidine derivatives R 0515 Efficient One-Pot Synthesis of 2-Oxo-1,9a-dihydro-2H-pyrido[1,2-a]pyrimidine Derivatives. -Slow addition of acetylenic esters (III) to a mixture of pyridines (I) and isocyanates (II) causes spontaneous reaction between the three components to afford the title derivatives (IV) in excellent yields. The reaction is performed under neutral conditions without any activation or modification. The simplicity of this one-pot method is an interesting alternative to other procedures. -(ADIB*, M.; YAVARI, H.; MOLLAHOSSEINI, M.; Tetrahedron Lett. 45 (2004) 8, 1803-1805; Dep. Chem., Fac. Sci., Tehran Univ., Tehran, Iran; Eng.) -H. Hoennerscheid 23-174