One-pot synthesis of 4,4ʹ-(arylmethylene)-bis-(3-methyl-1-phenyl-1H-pyrazol-5-ols) catalyzed by Brönsted acidic ionic liquid supported on nanoporous Na+-montmorillonite

Na+-MMT-[pmim]HSO4, obtained from the immobilization of 1-methyl-3-(trimethoxysilylpropyl)-imidazolium hydrogen sulfate Brönsted acidic ionic liquid on nanoporous Na+-montmorillonite, was used as catalyst for the simple and efficient synthesis of 4,4'-(arylmethylene)-bis-(3-methyl-1-phenyl-1H-pyrazol-5-ol) derivatives via the one-pot condensation of phenyl hydrazine, ethyl acetoacetate and aldehydes.