An eco-friendly and very low catalyst loading continuous condensation of primary amines and 1,3 Di carbonyl compounds: Synthesis of enaminones and enaminoesters by microreactor technology

Abstract

Herein, an efficient eco-friendly protocol is reported for the continuous synthesis of enaminones using a microreactor device in the presence of a catalytic amount of cerium (III) trichloride (1 mol%) in Propylene carbonate (PC) as a non-toxic solvent. Moreover, continuous separation of the corresponding product, and recycling of the catalyst-solvent system with water is another promising advantage of this technique. Indeed, the separation of the product by water allows any required catalyst and solvent to be reapplied in the next run. In addition, this microfluidic system enabled turnover frequency (TOF) of up to 2940 h⁻¹ for the corresponding products. The employment of these environment friendly facilitates produce the products with an excellent isolated yield up to 98%. This method performs efficiently, and would extent future applications of continuous organic, inorganic and biochemical reactions in green chemistry.

Graphical Abstract