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Asymmetric 1,2-addition of dialkylzinc reagents to α,β-unsaturated N-tosylaldimines was catalyzed by copper salt in the presence of chiral imidazolium salts having a pyridine ring, which were derived from amino acid, to afford the corresponding chiral allylic amines with up to 91% ee in reasonably high yields. The chiral N-heterocyclic carbene (NHC) ligand played an important role in controlling chemoselectivity.

Various chiral oxazolidinones (Evans’ oxazolidinones) have been employed as effective chiral auxiliaries in the asymmetric alkylation of different enolates. This strategy has been found promising and successful when used as the key step (steps) in the total synthesis of several biologically active natural products. In this report, we try to underscore the applications of oxazolidinones as chiral auxiliaries in asymmetric alkylation, and particularly in the crucial chiral inducing steps in the total synthesis of natural products that show biological activities. Chiral auxiliaries are generally considered reliable compounds with well-known configurations, enabling and controlling the synthesis of a large number of enantiomerically pure compounds in a time-efficient manner. Consequently, the use of chiral auxiliaries are frequently considered a method of choice in the early phases of drug discovery.

A green and economic aerobic oxidation of benzylic, (hetero)aryl, and allyl alcohols is developed.

A chiral phase transfer catalyst is used in the reaction of 2-cyanobenzaldehyde with active methylene compounds.

A series of title compounds is prepared as building blocks for functional chiral molecules.

Enantiopure β-amino acid esters and chiral amides are simultaneously prepared by the title protocol.

Bifunctional catalysts bearing amino and urea functional groups have been applied for a novel, highly enantioselective synthesis of axially chiral isoquinoline N-oxides, which are promising chiral ligands or organocatalysts in organic synthesis. This is the first example of highly enantioselective synthesis of axially chiral biaryls by bifunctional organocatalysts. Good-to-excellent enantioselectivities were obtained with a range of substrates.

A Pd-catalyzed intermolecular asymmetric hydroamination of styrenes was developed to give various chiral benzyl amides exclusively, in which the oxidation-stable pyridine-oxazoline was used as the chiral ligand to provide moderate to good enantioselectivities.

The syn/anti selectivity pattern is dictated by a suitable substrate and/or ligand selection.

The reaction starts from aromatic ketones, (hetero)aryl or cycloalkyl aldehydes and primary or secondary alkyl amines or (hetero)aryl amines.

A highly efficient chiral gold phosphate-catalyzed tandem hydroamination/asymmetric transfer hydrogenation reaction is described. A series of chiral tetrahydroquinolines were obtained in excellent yields and enantioselectivities. In this reaction, the gold catalyst enables both the hydroamination step as a π-Lewis acid and the asymmetric hydrogen-transfer process as an effective chiral Lewis acid.

Hydrophilic coordinating chiral ionic liquids with an amino alcohol substructure were developed and efficiently applied to the asymmetric reduction of ketones. Their careful design and adaptability to the desired reaction conditions allow for these chiral ionic liquids to be used as the sole source of chirality in a ruthenium-catalyzed transfer hydrogenation reaction of aromatic ketones. When used in this reaction system, these chiral ionic liquids afforded excellent yields and high enantioselectivities.

Achiral ethylenediamine forms chiral structures spontaneously when crystallized as the sulfate salt.

A highly enantioselective oxidative dearomatization of 1-naphthol derivatives (Kita spirolactonization) catalyzed by chiral hypoiodite species prepared in situ from chiral quaternary ammonium iodide in the presence of hydrogen peroxide is reported.

Nitrogen-, phosphorus-, and oxygen-based ligands with chiral backbones have been the historic workhorses of asymmetric transition-metal-catalyzed reactions. On the contrary, sulfoxides containing chirality at the sulfur atom have mainly been used as chiral auxiliaries for diastereoselective reactions. Despite several distinct advantages over traditional ligand scaffolds, such as the proximity of the chiral information to the metal center and the ability to switch between S and O coordination, these compounds have only recently emerged as a versatile class of chiral ligands. In this Review, we detail the history of the development of chiral sulfoxide ligands for asymmetric catalysis. We also provide brief descriptions of metal–sulfoxide bonding and strategies for the synthesis of enantiopure sulfoxides. Finally, insights into the future development of this underutilized ligand class are discussed.

A Cu-catalyzed [3 + 2] cycloaddition of exomethylene substituted indolinones (I) and (IV) with imino esters (II) and (V) is investigated in the presence of chiral pyridine-based chelating ligands such as (PDB) to yield spirocyclic compounds (III) and (V).

This new, efficient tandem process for the transformation of N-substituted amidines into secondary amides is applicable for aliphatic and (hetero)aromatic compounds.

Chiral biaryl halogenides [(II) and (IV)] are synthesized with high enantioselectivities by chiral phosphoric acid catalyzed asymmetric iodination or chlorination followed by kinetic resolution-type asymmetric bromination.

Attempts upon an asymmetric version of the methodology using chiral pyridine N-oxide catalysts are in progress.

We report a highly enantioselective hetero-Diels–Alder reaction of α-keto esters and isatins catalyzed by chiral calcium BINOL-derived phosphates. The structure of the catalyst is detailed by X-ray crystal structure analysis.

(R,R)-Diisopropyl tartrate is used as a source of chirality in the inter- or intramolecular reductive aldol-type synthesis of β-hydroxy esters, however, the chiral induction is rather poor.

Acyclic nucleosides and their phosphonates possess significantly antiviral and cytostatic activities. For acyclic nucleosides and their phosphonates, the introduction of a chiral group to their side chain or the absolute configuration of the chiral atom could affect their biological activities obviously. Thus, the asymmetric synthesis of chiral acyclic nucleosides and their phosphonates has received continuous attention. The previous reports mainly focus on employing the chiral pool and chiral auxiliary methods for the synthesis of chiral acyclic nucleosides and their phosphonates. In contrast, the asymmetric catalysis methods for the synthesis of acyclic nucleosides and their phosphonates are still in the beginning. This digest paper will serve to highlight the significant progress that has been made in these areas.

The asymmetric synthesis of both the enantiomers of chiral amines (III) from the same chiral sulfinylaldimine source (I) is achieved by simply changing the organometallic reagent in the addition reaction.

The first example of the enantioselective conjugate addition of alkenes to enones, catalyzed by chiral primary amines are reported.The reaction is enabled by chiral primary amines through a typical iminium ion cycle.

Novel chiral C2-symmetric salen ligands bearing morpholine moieties are designed and synthesized.

Chiral sulfilimines are prepared by rhodium-catalyzed intermolecular amination of thioethers with the readily available N-mesyloxycarbamate (I).

Results of preliminary trials of an asymmetric fluorination using chiral aryl iodides are also presented.

The chiral δ-lactone (IIIe) is an important key intermediate in the total synthesis of the antidepressant drug (-)-paroxetine.

The new method for the C—H amidation and amination of (hetero)arenes employs a readily removable directing group.

The synthesis of anti-alcohols (III) and syn-alcohols (VI) is carried out by a phenolic kinetic resolution of corresponding epoxides (I) and (V) in the presence of a chiral cobalt salem catalyst.

The title chiral dipoles generated in situ from the corresponding imines, chiral phosphites, and acid chlorides, undergo intramolecular alkene cycloaddition with high enantioselectivity.

Chiral ligand-modified metal nanoparticles possess an attractive potential for application in asymmetric synthesis. This article focuses on chiral-nanoparticle-catalyzed asymmetric C–C bond formation reactions and discusses the nature of the active species.

The rapid evaluation of libraries of chiral phosphine ligands with a set of simple cobalt precursors is reported.

A novel gold-catalyzed tandem cycloisomerization/dimerization of chiral homopropargyl sulfonamides is developed.

The reaction is the first example of an enantioselective C—H iodination leading to chiral iodinated diarylmethylamines.

The intermediate chiral iminium ethers, generated in situ via Claisen rearrangement of chiral amides, are directly converted into enantioenriched α-allyl carboxylic acids or aldehydes.

Chiral bidentate ligands derived from (S)-mandelic acid and chiral mono-alkylated aziridines are investigated as ligands for the asymmetric Ni-catalyzed conjugate addition of diethylzinc to enones.

The aldol reaction of dioxanone with the chiral aldehyde (I) in the presence of D- or L-proline allows access to the title compounds.

The study shows a proof for the concept that sulfoxides are used both as a directing group and a chiral auxiliary.

This article covers N-acyl chiral auxiliary-based approaches to the asymmetric synthesis of enantiopure aldehydes and ketones. The use of diastereoisomerically pure N-acyl derivatives of chiral auxiliaries (including chiral Weinreb amide equivalents) and their conversion to the corresponding enantiopure aldehydes and ketones in a single synthetic operation by treatment with a hydride reducing agent or an organometallic reagent, respectively, are highlighted.

The developed title reaction affords different substituted chiral enantioenriched propargylic alcohols.

This method uses a chiral primary amine and a chiral phosphoric acid as an organocatalytic system to yield the products (III) with high enantioselectivities.

This reaction yields chiral benzofuranones via desymmetrization from prochiral α,α-diaryl acids by employing N-protected amino acids as chiral ligands.

Three pyridine stabilized palladium N-heterocyclic carbenes are developed to catalyze the amination of (hetero)aryl chlorides.

The synthesis of chiral oxazolidinone scaffolds from readily available oxabicyclic alkenes is described.

A highly regio- and enantioselective Cu-catalyzed hetero-allylic asymmetric alkylation with functionalized Grignard reagents is developed.

Chiral silyl dienol ether (I) reacts with acetals in the presence of a Lewis acid to afford syn-adducts such as (III) and (V) as major products.

This method yields chiral propargylic alcohols and tolerates a variety of functional groups.

Chiral pyrazolines and their derivatives are a common motif in biologically active compounds.

Key feature in the preparation of chiral piperidines is the activation of simple pyridines as N-benzyl-pyridinium bromides.