Metal and Ligand‐Free Approach Towards the Efficient One‐Pot Synthesis of Dipyridopyrimidinimine Derivatives

We report a facile, expeditious, user‐friendly, and convenient metal‐free synthesis employing base catalysis in a one‐pot procedure to construct 11 H ‐dipyrido[1,2‐ a : 3′,2′‐d]pyrimidin‐11‐imine derivatives. This protocol involves a domino process leading to the formation of double C−N bonds utilising KO t Bu as the base and DMAc as the superior solvent at 25 °C for 2 h. The versatility of this methodology was demonstrated by its successful application to substrates with both electron‐withdrawing and electron‐donating functional groups, yielding novel functionalized stable 11 H ‐dipyrido[1,2‐ a : 3′,2′‐d]pyrimidin‐11‐imine derivatives in good to excellent yields. Additionally, we have discussed a plausible reaction pathway for the synthesis.