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This update describes a highly efficient organocatalytic aldol reaction of ketones and β,γ-unsaturated α-keto esters for constructing the chiral tertiary alcohol motif. With the application of 9-amino(9-deoxy)epi-Cinchona alkaloid and an acidic additive as catalysts, both acyclic and cyclic ketones react with β,γ-unsaturated α-keto esters smoothly to afford aldol adducts in good to excellent yields and asymmetric induction. This protocol offers a new pathway for the construction of adjacent chiral carbon centers and the synthesis of chiral β-hydroxy carbonyl compounds.

A new strategy was developed for the synthesis of a valuable class of α-aminomethylacrylates via the Baylis―Hillman reaction of different aldehydes with methyl acrylate followed by acetylation of the resulting allylic alcohols and S N 2'-type amination of the allylic acetates. Asymmetric hydrogenation of these diverse olefinic precursors using rhodium(Et-Duphos) catalysts provided the corresponding β 2 -amino acid derivatives with excellent enantioselectivities and exceedingly high reactivities (up to >99.5% ee and S/C=10,000). The first hydrogenation of (Z)-configurated substrates was studied for the synthesis of β 2 -amino acid derivatives. The high influence of the substrate geometry and steric hindrance on the reactivity and enantioselectivity was also disclosed for this reaction. This protocol provides a highly practical, facile and scalable method for the preparation of optically pure β 2 -amino acids and their derivatives under mild reaction conditions.

Two types of catalysts [RuL-(benzene)Cl]Cl and Ru(OCOCH 3 ) 2 L with the dipyridylphosphine ligands P-Phos and Xyl-P-Phos were applied in the asymmetric hydrogenation of α,β-unsaturated carboxylic acids. The cationic complexes [RuL(benzene)Cl]Cl were found to be superior to the corresponding neutral complex Ru(OCOCH 3 ) 2 L in this type of reactions. The catalysts exhibited excellent activities and enantioselectivities (up to 97% ee) in the asymmetric hydrogenation.

The development of highly enantioselective catalysts involving Cu(OTf) 2 and chiral camphorsulfonamides for the alkynylation of ketone is described. The influences of Lewis acids, reaction conditions and chiral ligands on the outcome of the reaction are discussed. The best enantioselectivity (up to 97% ee) was obtained in the alkynylation of 2'-chloroacetophenone. The scope of the reaction is also examined.

The chiral atropisomeric diphosphane ligand (S)-BisbenzodioxanPhos was found to be highly effective in the co-operative processeses of aldehyde decarbonylation and cascaded enantioselective Pauson-Khand-type reactions. Various 1,6-enynes were transformed to the corresponding bicyclic cyclopentenones in good yields and enantiomeric excesses (up to 96% ee). The attractive feature of this new Rh-catalyzed homogeneous dual catalysis system is that the reaction can be performed in alcoholic solution.