A mixture of 6-pyridin-3-yl-1,3-dihydro-indol-2-one (100 mg, 0.5 mmol), 4-methoxy-3-thiophen-2-yl-benzaldehyde (110 mg, 0.5 mmol) and piperidine (0.23 mL) in ethanol (4 mL) was heated to reflux and stirred overnight. The reaction mixture was then cooled and diluted with ether to afford a precipitate which removed by filtration. Thefiltrate was column chromatographed (eluant—isopropanol/dichloromethane) to give 30 mg (15%) of 3-(4-methoxy-3-thiophen-2-yl-benzylidene)-6-pyridin-3-yl-1,3-dihydroindol-2-one as a yellow solid.
