N-ethyltetramethylguanidinium ionic liquid [ETMG][EtSO3] as organocatalyst and solvent for facile amide synthesis by formyl-transfer with N-formyl-saccharin

Abstract

We report a simple and highly efficient, acid and metal free, method for the synthesis of libraries of primary and secondary formamides employing N-ethyltetramethylguanidinium IL, [ETMG][EtOSO3] as dual organocatalyst and solvent, and N-formyl-saccharin (N-formyl-SAC) as formyl-transfer agent. Good to excellent isolated yields are achieved at r.t. within minutes under sonication. A rational for the efficacy of this organocatalyst is provided by DFT computations.