Environmentally benign synthesis of 3-methyl-4-[(1,3-diphenyl-1H-pyrazol-4-yl)-methylene]-1-phenylpyrazolin-5-(4H)-ones in an ionic liquid
Abstract
The condensation of 1,3-diphenyl-1H-pyrazole-3-carbaldehydes with 3-methyl-1-phenylpyrazolin-5-(4H-)-one in an ionic liquid (ethylammonium nitrate) afforded 3-methyl-4-[(1,3-diphenyl-1H--pyrazolo-4-yl)methylene]-1-phenylpyrazolin-5-(4H-)-ones in an excellent yield at room temperature.