KF‐Alumina Catalyzed One‐Pot Synthesis of Pyrido[2,3‐d]Pyrimidine Derivatives

A series of pyrido[2,3‐d]pyrimidine derivatives was synthesized by the reaction of arylaldehyde, malononitrile, and 4‐amino‐2,6‐dihydroxylpyrimidine in ethyl alcohol at 80°C catalyzed by KF‐Al2O3. Compared with other synthetic methods, this new method has the advantage of easier workup, milder reaction conditions, and good yields.