Facile One‐pot, Three‐component Synthesis of Novel Bis‐heterocycles Incorporating 5H‐chromeno[2,3‐b]pyridine‐3‐carbonitrile Derivatives

Novel bis-chromeno[2,3-b]pyridine derivatives were synthesized with good yields by a clean and efficient methodologies involving one-pot three-component synthesis of bis-aldehydes, malononitrile dimer, and dimedone in the presence of piperidine as a catalyst in EtOH. Depending on the length and position of the spacer in the bis-aldehyde derivatives 1, the reactions proceeded to give either the bis(2,4-diamino-tetrahydro-5H-chromeno[2,3-b]pyridine-3-carbonitriles) 4 or bis(4-amino-2,6-dioxo-hexahydro-2H-chromeno[2,3-b]pyridine-3-carbonitriles) 5. All of the new compounds have been characterized by spectral data.