Organocatalyzed Asymmetric Cascade Michael/Michael Reaction of α‐Alkylidene Succinimides with a 2‐(Trifluoromethylmethylene)indane‐1,3‐dione

A diaminomethylenemalononitrile organocatalyst efficiently promoted asymmetric cascade Michael/Michael reactions between a 2‐(trifluoromethylmethylene)indane‐1,3‐dione derivative and α‐alkylidene succinimides, resulting in spiroindane‐1,3‐dione derivatives. These derivatives feature four consecutive carbon stereocenters, including one stereocenter with a trifluoromethyl substituent, and were formed in high yield with excellent enantioselectivity (up to 94 % ee). This study marks the first successful example of using methyleneindane‐1,3‐dione derivatives, bearing alkoxycarbonyl and trifluoromethyl groups at the β‐position, as Michael acceptors.