Bifunctional C2-symmetric ionic liquid-supported (S)-proline as a recyclable organocatalyst for Mannich reactions in neat condition

Abstract A bi-functional C2-symmetric ionic liquid-supported (S)-Proline organocatalyst [BHEDIMP][CF3CO2] has been designed and synthesized for the first time. The novel C2-symmetric organocatalyst [BHEDIMP][CF3CO2] (4 mol%) was employed for the one-pot multi-component Mannich reactions comprising of substituted acetophenones, arylamines, and aryl aldehydes to yield racemic β-amino ketones derivatives in neat conditions. This present synthetic method is highlighted by numerous advantages such as low catalyst loading percentage, solvent-free synthesis, short reaction times, easily accessible substrates, and devoid of chromatography purification. The supported C2-symmetric organocatalyst was recycled and reused six times without substantial damage to its catalytic efficiency.