PEPPSI-SONO-SP2: a new highly efficient ligand-free catalyst system for the synthesis of tri-substituted triazine derivatives via Suzuki–Miyaura and Sonogashira coupling reactions under a green approach

The pyridine containing decidedly resourceful Pd-N-heterocyclic carbene complex, PEPPSI-SONO-SP2, is being used as a first class catalyst for Suzuki-Miyaura and Sonogashira cross coupling reactions. The catalyst showed a great performance in the consecutive reactions of 4-(4',6'-dichloro-1,3,5-triazin-2-yl)morpholine with various boronic acids and terminal acetylenes under mild and green conditions (ethanol: water) even in the absence of a blanket of inert atmosphere. Significantly, all the synthesized compounds were found to be new and the catalyst is used for the first time in these reactions. The findings suggest that 0.1 mol% of catalyst is sufficient, recyclable and can be reused for six cycles.