An Indium(III) Triflate Catalyzed Simple and Efficient One-Pot Synthesis of Substituted 3,3-Diaryloxindoles and Bis(indol-3-yl) methanes from Indoles and Isatins or Aryl Aldehydes

Indium(III) triflate was found to be an efficient metal catalyst for the electrophilic substitution reaction of substituted indoles with various isatins or aryl aldehydes in acetonitrile solvent to afford the corresponding 3,3-diaryloxindoles or bis(indol-3-yl)methanes, respectively, in high yields at room temperature. This new procedure has remarkable features such as experimental simplicity, high conversions, good to excellent yields, short reaction times, and simple workup procedures