Reinvigorating aza-Michael reactions under ionic liquid catalysis: a greener approach
Silvia Izquierdo1, Pedro Cintas2, Carlos J Durán-Valle2
1Department of Organic and Inorganic Chemistry, School of Technology and INTERRA-Sustainable and Environmental Chemistry Lab, Universidad de Extremadura, 10003-Cáceres, Spain. sizquierdo@unex.es.
Abstract:
Cholinium α-amino carboxylates, which debuted in the ionic liquid arena over a decade ago, exhibit superior stability and suitable physical properties relative to other RTILs. Although synthetic pursuits in such media, leveraging their dual role as solvents and catalysts, have been scarce so far, we herein illustrate their catalytic advantage in aza-Michael reactions in terms of low loading, acceleration and improved yields with respect to conventional conditions and other imidazolium-based ILs. These highly structured salts most likely act through multiple and cooperative non-covalent interactions. These mechanistic features have also been investigated through high-level computational analyses as well.
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