One-Pot Site-Selective Sonogashira Cross-Coupling–Heteroannulation of the 2-Aryl-6,8-Dibromoquinolin-4(1 H )-Ones: Synthesis of Novel 6- H -Pyrrolo[3,2,1- ij ]Quinolin-6-Ones

The 2-aryl-6,8-dibromoquinolin-4(1H)-ones were subjected to site-selective Sonogashira cross-coupling with terminal acetylenes as models for Csp²-Csp bond formation in the presence of Pd/C–PPh₃ and CuI as catalysts and K₂CO₃ as a base in dioxane to afford the 2-substituted 4-aryl-8-bromo-4H-pyrrolo[3,2,1-ij]quinolin-6-ones. These were, in turn, subjected to Suzuki–Miyaura cross-coupling with 4-fluorophenylboronic acid as coupling partner to afford the 2-substituted 4,8-diaryl-4H-pyrrolo[3,2,1-ij]quinolin-6-ones.