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The enantioselective synthesis of a series of C2 -symmetric 3,3'-diarylated 1,1'-spirobiindane-7,7'-diols (3,3'-diaryl-SPINOLs) was developed by sequential Rh-catalyzed twofold asymmetric conjugate arylation/BF3 -promoted diastereoselective spirocyclization (>20:1 d.r. and >99 % ee for all examples). Some phosphoramidite ligands were prepared from the 3,3'-Ph-SPINOL and applied to several catalytic asymmetric reactions, and the 3,3'-diarylated ligands showed higher enantioselectivities than the privileged nonsubstituted ligands.

A general method to access diverse chiral phenols by rhodium-catalyzed asymmetric conjugate arylation using hydroxylated arylboronic acids in ethanol was developed. Recycling of the rhodium catalyst by flash chromatography on silica gel was feasible in this system. The synthetic utility of the strategy was demonstrated by efficient synthesis of chiral drug tolterodine.

The enantioselective synthesis of 2-amino-4H-chromenes via the cascade rhodium-catalysed conjugate addition/hetero Thorpe–Ziegler reaction is reported. Moderate to good yields (up to 98%) and high enantioselectivities (up to 92% ee) were obtained with a chiral diene-coordinated rhodium complex as the catalyst. This protocol remedies the methodological deficiency in the asymmetric synthesis of 4-aryl 2-amino-4H-chromenes.

A new type of planar chiral Shvo catalysts, where the chirality is based solely on different substitution flanking the CO function, was prepared and used for transfer hydrogenation of imines and ketones. The reduction of ketimines represented by N-(1-phenylethylidene)aniline and prochiral ketones such as phenyl trifluoromethyl ketone with 2-propanol was efficiently catalyzed by 0.5 mol% of the chiral Shvo catalyst to give high yields of the corresponding reduction products with the enantioselectivities in the range 45% to 64% ee.

Asymmetric conjugate alkynylation of cyclic α,β-unsaturated carbonyl compounds (ketones, esters, and amides) was realized by use of diphenyl[(triisopropylsilyl)ethynyl]methanol as an alkynylating reagent in the presence of a rhodium catalyst coordinated with a new chiral diene ligand (Fc-bod; bod=bicyclo[2.2.2]octa-2,5-diene, Fc=ferrocenyl) to give high yields of the corresponding β-alkynyl-substituted carbonyl compounds with 95-98% ee.

A phosphine-catalyzed novel [4+2] annulation process was devised employing allene ketones as C2 synthons and β,γ-unsaturated α-keto esters as C4 synthons. In the presence of an L-threonine-derived bifunctional phosphine, 3,4-dihydropyrans were obtained in high yields and with virtually perfect enantioselectivities. The synthetic value of the dihydropyran motif was demonstrated by a concise preparation of an anti-hypercholesterolemic agent.

Asymmetric N-alkylations of isatins with enals were shown to be feasible via a prolinol-catalyzed iminium activation, and N-alkylated isatins were obtained in good yields and with excellent enantioselectivity. The biologically useful N-alkylated isatins also served as valuable synthetic precursors, and could be readily converted to chiral N-alkylated indole derivatives. The described method provides a novel entry to access optically enriched N-alkylated isatins and indole derivatives.

The Rauhut–Currier (RC) reaction represents an efficient method for the construction of carbon–carbon bond in organic synthesis. However, the RC reactions involving allenoate substrates are very rare, and in particular, asymmetric intramolecular RC reaction of allenoates is yet to be discovered. Here, we show that the intramolecular RC reaction proceeds smoothly in the presence of 1 mol% β-ICD, and bicyclic lactones are obtained in high yields and with excellent enantiomeric excesses. With the employment of γ-substituted allenoates as racemic precursors, a novel dynamic kinetic resolution of allenes via RC reaction is observed, which allows for facile synthesis of highly enantiomerically enriched allenes., The Rauhut-Currier reaction is a powerful method to form carbon-carbon bonds. Here, the authors report an enantioselective intramolecular variant between alkenes and allenoates, giving access to highly functionalised bicyclic lactones in excellent enantiomeric excess.

This is the first highly enantioselective Michael addition of oxindoles catalyzed by chiral phosphines.

Organocatalysis: a modified Feist-Bénary reaction employing acyclic β-ketoesters as the dinucleophile and (E)-β,β-bromo nitrostyrenes as the dielectrophile was developed for the asymmetric synthesis of 2,3-dihydrofurans. L-Threonine-derived tertiary amine/thiourea catalysts were found to be the most efficient catalysts, inducing the reaction in a highly enantioselective manner (TBDPS=tert-butyldiphenylsilyl).

Phthalides were used for the first time in the allylic alkylation reactions with MBH carbonates for the creation of chiral 3,3-disubstituted phthalides. Highly enantioselective regiodivergent synthesis of γ-selective or β-selective allylic alkylation products was achieved by employing bifunctional chiral phosphines or multifunctional tertiary amine-thioureas as the catalyst, respectively. It was demonstrated that proper selection of catalysts and reaction conditions would differentiate an S(N)2'-S(N)2' pathway and an addition-elimination process, yielding different regioisomers of the allylic alkylation products in a highly enantiomerically pure form.

An efficient direct asymmetric aldol reaction between hydroxyacetone and β,γ-unsaturated α-keto esters has been successfully developed. In the presence of 9-amino-9-deoxy-epi-cinchonine and trifluoroacetic acid, the direct aldol reaction of O-protected hydroxyacetone proceeded in a highly enantioselective manner, affording the desired adducts containing a chiral tertiary alcohol in high yields and with excellent enantioselectivities. The aldol products obtained are valuable precursors for the synthesis of 2-substituted glycerol derivatives.

A novel [4 + 2] annulation process is developed employing β,γ-unsaturated α-keto esters as C4 building blocks and allene ketones as C2 synthons.

Michael addition of various sulfenyloxindoles to nitroolefins proceeds stereoselectively using a quinine catalyst bearing a silyl-threonine moiety to give oxindoles with a 3-sulfenyl-substituted quaternary center in excellent yields and with high diastereoselectivities and excellent enantioselectivities.

Chiral aza-ortho-xylylene intermediates were efficiently generated from 3-chloro-3-substituted oxindole precursors. The first intramolecular trapping of chiral aza-ortho-xylylene intermediates led to a highly asymmetric synthesis of 3-spirocyclopropyl-2-oxindoles.

The first asymmetric conjugate addition of title compounds (I) to vinyl sulfones (II), promoted by a tertiary amine-thiourea bifunctional catalyst is described.

With the employment of a threonine-incorporating multifunctional catalyst 9, Michael addition of 3-sulfenyloxindoles to nitroolefins proceeded stereoselectively, leading to the formation of oxindoles with a 3-sulfenyl-substituted quaternary center in excellent yields, and with high diastereoselectivities and excellent enantioselectivities.

This is the first highly enantioselective Michael addition of oxindoles catalyzed by chiral phosphines.

This method uses β-ketoesters as substrates and a L-threonine-derived tertiary amine/thiourea bifunctional organocatalyst to yield functionalized 2,3-dihydrofurans with good yields and enantioselectivities.

The first highly enantioselective decarboxylative addition of β-ketoacids to isatins mediated by a bifunctional tertiary amine–thiourea catalyst has been developed, allowing facile synthesis of biologically important 3-hydroxy oxindoles in good yields and excellent enantioselectivities. The method reported represents a valuable approach of utilizing β-ketoacids as synthetic equivalents of aryl/alkyl methyl ketone enolates.

The direct organocatalytic asymmetric cyclopropanation reaction of oxindoles by employing oxindoles as C1 synthon and bromonitroolefins as a convenient C2 synthon is described.

Phthalides are used for the first time in allylic alkylation reactions with Morita—Baylis—Hillman carbonates for the preparation of chiral 3,3-disubstituted phthalides.

Enantioselective preparation of some synthetically and biologically valuable 3(2H)-furanones is achieved using a novel tertiary amine/thiourea catalyst.

The direct organocatalytic asymmetric cyclopropanation reaction of oxindoles by employing oxindoles as C1 synthon and bromonitroolefins as a convenient C2 synthon is described.

An efficient direct asymmetric aldol reaction between hydroxyacetone and β,γ-unsaturated α-keto esters has been successfully developed. In the presence of 9-amino-9-deoxy-epi-cinchonine and trifluoroacetic acid, the direct aldol reaction of O-protected hydroxyacetone proceeded in a highly enantioselective manner, affording the desired adducts containing a chiral tertiary alcohol in high yields and with excellent enantioselectivities. The aldol products obtained are valuable precursors for the synthesis of 2-substituted glycerol derivatives.

Chiral aza-ortho-xylylene intermediates were efficiently generated from 3-chloro-3-substituted oxindole precursors. The first intramolecular trapping of chiral aza-ortho-xylylene intermediates led to a highly asymmetric synthesis of 3-spirocyclopropyl-2-oxindoles.