Novel pyrimido[4,5-𝑏]quinolines and pyrido[2,3-𝑑:6,5-𝑑']dipyrimidine derivatives were synthe-sized in one-pot, three-component approach using sulfonic acid supported on hydroxyapatite-encapsulated-𝛾-Fe2O3 [𝛾-Fe2O3 @HAp-SO3H] as magnetically recoverable nanocatalyst. The protocol provided a rapid, useful and green method for the preparation of the products in short reaction times and high yields.
