An interesting asymmetric organocatalytic cascade reaction of 3-hydroxyoxindoles with coumarins was accomplished by chiral bisguanidinium hemisalt. A series of enantioenriched spirobenzofuran indolinones were afforded in high yields with high diastereo- and enantioselectivities. The reaction was disclosed to involve in several steps: intermolecular Michael reaction, transesterification, retro-Michael reaction, substitution and decarboxylation, then an intramolecular Michael reaction to yield the product, in which the final step is disclosed to be stereo-determining step. In addition, it provided a facile route for the late-stage modification of several drug molecules via installation of spirobenzofuran indolinone scaffold.

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