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 alpha-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 beta-position, as Michael acceptors.