ChemInform Abstract: Simultaneous Exploration of TBAF·3H2O as a Base as well as a Solvating Agent for the Palladium Catalyzed Suzuki Cross-Coupling of 4-Methyl-7-nonafluorobutylsulfonyloxy Coumarins under Microwave Irradiation.

Abstract A concise, efficient and facile protocol for the synthesis of a variety of 4-methyl-7-aryl/heteroaryl coumarins has been developed by utilizing the palladium catalyzed Suzuki cross-coupling reaction of 4-methyl-7-nonafluorobutylsulfonyloxy coumarin with a wide range of electronically diverse boronic acids under microwave irradiation. In the presence of a suitable catalyst, ligand and base, the coupling reaction proceeded smoothly to give the biaryls in satisfactory to exceptional yields. The dual role of TBAF·3H 2 O as a base as well as a solvating agent and the utilization of dppp as a ligand with moderate bite angle (91°) were found to be instrumental for the success of the reaction. Prominent features of this optimization conditions include: shorter reaction times, good to excellent yield and exceptional tolerance to a wide variety of functional groups.