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An efficient enantioselective conjugate addition of malononitrile to a range of β-substituted 2-enoylpyridines catalyzed by cinchona alkaloid-based bifunctional urea catalysts has been developed. Both enantiomers of the products could be achieved with the same level of enantioselectivity by using pseudoenantiomeric catalysts in up to 97% ee and in excellent yields. One of the enantioenriched products has been transformed to a highly functionalized piperidone derivative.

A potential pharmacologically active chiral 3-substituted 4-hydroxy-2-oxo-2H-chromene skeleton has been synthesized by enantioselective Michael addition catalyzed by PYBOX-DIPH-Zn(OTf)(2) complex. The methodology has successfully been employed in the synthesis of (R)-Warfarin and another related compounds.

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A highly enantioselective synthesis of chiral chroman derivatives via an oxa-Michael-Michael cascade reaction has been developed using a bifunctional thiourea organocatalyst. The products were obtained with excellent enantioselectivities (up to >99%), good yields (up to 95%), and diastereoselectivities (up to 5:1).

A mild, efficient method for the synthesis of diaryl diazaphosphonates via 1,6-hydrophosphonylation/aromatization of p-quinone methides (p-QMs) with N-heterocyclic phosphine-thioureas has been developed. This transformation proceeds without any additive or catalyst under mild reaction conditions and tolerates a wide range of p-QMs. This methodology provides a straightforward access to diaryl phosphonate derivatives in good to excellent yields (up to 99%).

The isomerization of dienyl alcohols and polyenyl alkyl ethers catalyzed by TBD (1,5,7triazabicyclo[4.4.0]dec-5-ene) under metal-free conditions is presented. Two reaction pathways have been observed. For dienyl alcohols, the reaction proceeds by a [1,3]-proton shift to give γ,δ-unsaturated ketones exclusively. On the other hand, the reaction with polyenyl alkyl ethers gives the corresponding conjugated vinyl ethers in good yields (up to 85%), with regioselectivities up to >20:1. Experimental and computational investigations suggest that the mechanism proceeds through consecutive "chain-walking" proton shifts ("base walk") mediated by TBD.