The first example of bifunctional oxindole‐chromone C3 synthon directed organocatalytic cascade cycloaddition reaction is developed, serving as a fruitful strategy for the facile access of optically active tetrahydrocyclopenta[b]chromanone bearing one spirooxindole with five contiguous stereocenters. All the products are smoothly obtained with up to 83% yield, >20:1 d.r. and >99% ee. This is also the first asymmetric catalytic construction of tetrahydrocyclopenta[b] chromanone and tetrahydrocyclopenta[b]chromanone‐spirooxindole scaffold, thus to facilitate the search for new bioactive entities.magnified image

Inspired by the chemistry and biology of chromone, a method for the construction of spirooxindole-based tetrahydrocyclopenta[b]chromanones is reported with good regio-and diastereoselectivity (all cases > 20:1 dr) and moderate yields (up to 67%). This method leads to the construction of four contiguous stereogenic tertiary centers and one spiro quaternary center via a one-step γ-regioselective cascade [3 + 2] cycloaddition of an oxindole-chromone synthon with 3-methyl-4-nitro-5-alkenyl-isoxazole.

Sequence. -Optimized conditions allow the diastereoselective reaction of 3-aminooxindoles with ,-dicyanoolefins to give the title compounds in high yields. -(LIU, X.-W.; YANG, J.; YANG, C.; HAN, W.-Y.; LIU*, X.-L.; ZHOU, Y.; YU, Z.-B.; YUAN, W.-C.; Tetrahedron Lett. 55 (2014) 51, 7110-7113, http://dx.

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