Synthesis of Chiral Dispiro-indolinone-pyrrolidine-rhodanines Using (R)/(S)-1-(2,4-dimethoxyphenyl)ethylamine

Abstract

The use of (R) or (S)-1-(2,4-dimethoxyphenyl)ethylamines as starting compounds makes it possible to obtain the individual enantiomers of dispiro-indolinone-pyrrolidine-rhodanines with a yield of up to 53% based on a three-step synthesis through the formation of 5-arylidenrhodanines with a chiral substituent at N(3) atom, their subsequent 1,3-dipolar cycloaddition with azomethine ylide generated in situ from isatin and sarcosine and chromatographic separation of the resulting diastereomers.