Ultrasound Promoted One-Pot Multicomponent Synthesis of Highly Functionalized Tetrahydropyridine Derivatives

The N-methyl pyridinium tosylate (NMPyTs) ionic liquid is used as an efficient, homogeneous, and recyclable catalyst for the synthesis of tetrahydropyridine derivatives via one-pot multi-component condensation of aromatic aldehyde, anilines, and β-ketoesters under ultrasonic irradiations. This protocol was successfully pertinent to a wide range of structurally diverse aromatic aldehydes, substituted anilines, and β-ketoesters. The major characteristics of this technique include operational simplicity, short reaction times, mild reaction conditions, and high yield. Importantly, NMPyTs can undergo up to three recycle runs without any noticeable loss of catalytic activity.