A Z/E-selective and enantioselective conjugate addition of oxindoles to butyl but-2-ynedioate derivatives has been developed, providing a facile access to enantioenriched multifunctional olefins, which can be further converted into 3,3a- dihydro-2H-pyrrolo[3,4-c]quinoline-1,4(5H,9bH)-dione derivatives via conventional operations.

http://onlinelibrary.wiley.com/doi/10.1002/adsc.201200715/full