An unexpected multi-component reaction to synthesis of 3-(5-amino-3-methyl-1H-pyrazol-4-yl)-3-arylpropanoic acids in ionic liquid

A new, one-pot, four-component condensation of 3-methyl-1H-pyrazol-5(4H)-one, ammonium acetate, aromatic aldehydes, and meldrum's acid in [bmim]BF4 as solvent is described for the synthesis of 3-(5-amino-3-methyl-1H-pyrazol-4-yl)-3-arylpropanoic acid derivatives. This methodology resulting in excellent isolated yields in short reaction time is characterized by simple work up procedure and little environmental impact.