A convenient solvent-free synthesis of γ-nitroketones and γ-nitroesters based on the reaction of nitroalkanes with α,β-unsaturated carbonyl compounds in the ultrasonically activated heterogeneous catalytic system 1-butyl-3-methylimidazolium tetra-fluoroborate ([bmim][BF4])/K2CO3 has been developed. The system retained its catalytic activity over three reaction cycles.
Michael additions - ionic liquids - catalysis - esters - ketones