Asymmetric Quadruple Aminocatalytic Domino Reactions to Fused Carbocycles Incorporating a Spirooxindole Motif

The efficient assembly of hydroindane derivatives incorporating a spirooxindole motif was realized via a new three-component domino reaction of (E)-4-(1-methyl-2-oxoindolin-3-ylidene)-3-oxobutanoates and two molecules of alpha,beta-unsaturated aldehydes under quadruple iminium-enamine-iminium-enamine catalysis. The complex products bearing six contiguous stereogenic centers were obtained in excellent stereoselectivities (96->99% ee, >99% de).