The asymmetric catalytic synthesis of naturally occurring and biologically active spiro compounds is a challenge for modern chemical methodology. Here we report the construction of spiro compounds through cascade [5+1] double Michael reactions between divinyl ketones and N-unprotected oxindoles or N-phenyl-protected pyrazolones catalyzed by a

Abstract(R)‐1,1′‐Binaphthyl‐2,2′‐diol (R‐BINOL) derived chiral phosphoric acids have been explored as organocatalysts for the asymmetric oxidation of a series of aryl alkyl sulfides and 1,3‐dithianes derived from aldehydes with aqueous hydrogen peroxide (H2O2) as the terminal oxidant. The enantiomerically enriched sulfoxides are obtained in moderate to excellent yield (up to 99%) with excellent diastereoselectivity (up to >99:1 dr) and moderate to good enantioselectivity (up to 91:9 er). In particular, the present protocol stereoselectively provides an efficient access to enantiomerically enriched aryl alkyl sulfoxides and dithioacetal mono‐sulfoxides, which strictly restrains the formation of the undesirable by‐products: sulfones or disulfoxides. The tracking experiments also verify that this approach proceeds via a direct sulfoxidation process, instead of a kinetic resolution route by overoxidation of the resulting sulfoxides.

Thiourea-modified cinchona alkaloids as bifunctional catalysts and a base could catalyze a stepwise [5+1] cyclization of divinyl ketones with nitromethane via double Michael additions, furnishing optically active 4-nitro-cyclohexanones with good yields, excellent diastereoselectivities (>20 : 1) and high enantiomeric ratios (up to 97 : 3).

The enantioselective nitroaldol reactions of isatins with nitroalkanes were smoothly carried out by organocatalysis. A C6′‐OH cinchona alkaloid derivative bearing a C9‐OBn group exhibited outstanding catalytic efficiency as an acid–base bifunctional catalyst for the nitroaldol reaction of isatins with nitromethane, providing 3‐hydroxy‐3‐(nitromethyl)indolin‐2‐ones in good yields (90–98 %) and with good to high enantiomeric excess values (72–95 %). The resultant oxindole derivatives are highly important for the synthesis of related natural products and pharmaceutically active compounds.

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