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Herein we report an enantioselective synthesis of ( R )-Sumanirole wherein an organocatalytic asymmetric aziridination of 2-nitrocinnamaldehyde was the key step.

A novel catalytic asymmetric synthetic method for making spirocyclohexadienones with an all-carbon quaternary spirocenter was developed based on the Pd-catalyzed intramolecular ipso -Friedel–Crafts allylic alkylation of phenols. When 5 mol % of the Pd catalyst and 12 mol % of (−)-9-NapBN (−)- 3e were used, the spirocyclic adduct was obtained with up to 93% ee, albeit with low chemical yield. On the other hand, when using 6 mol% of the Trost ligand ( R , R )- 3k , the spirocyclic adducts were obtained in good yields with up to 89% ee (diastereoselectivity = 9.2:1).

The asymmetric hydrogenation of α-amino-β-keto esters using ruthenium (Ru) anti -selectively proceeds via a dynamic kinetic resolution to afford anti -β-hydroxy-α-amino acids with high enantiomeric purities, which are important chiral building blocks for the synthesis of medicines and natural products. A mechanistic investigation has revealed that the Ru-catalyzed asymmetric hydrogenation takes place via the hydrogenation of the double bond in the enol tautomer of the substrate.

Asymmetric allylic aminations with aromatic amine nucleophiles using Pd–DIAPHOX catalyst systems are described. The asymmetric allylic aminations of various allylic carbonates proceeded using 2–5 mol % of the catalyst and BSA, providing the corresponding N-aryl chiral allylic amines in up to 99% ee for cyclic substrates, and in up to 97% ee for acyclic substrates.

A Pd-catalyzed asymmetric allylic alkylation of 2-substituted cycloalkenyl carbonates using a chiral diaminophosphine oxide is described. Asymmetric allylic substitution of various cyclic substrates proceeded using 5 mol % of Pd catalyst, 10 mol % of (S,RP)-Ph-DIAPHOX 1, 10 mol % of LiOAc, and N,O-bis(trimethylsilyl)acetamide (BSA), to afford the corresponding products in excellent yields with up to 92% ee.

The synthesis of novel P-stereogenic phenylphosphonamides 3 and 11 via an intramolecular nucleophilic substitution of P-stereogenic phosphoramide 8 is described. These compounds were used as chiral Lewis basic catalysts for the asymmetric allylation of benzaldehyde, providing the corresponding homoallylic alcohol derivatives in up to 54% ee.

The stereoselective synthesis of (3R,5R)-5-hydroxypiperazic acid, a component of naturally occurring antibiotic cyclodepsipeptides, and its diastereomer was achieved via the use of Lewis acid-promoted diastereoselective Strecker synthesis as a key step, in which an interesting stereochemical reversal of diastereoselectivity by the choice of Lewis acid catalyst was observed.

The highly efficient synthesis of (R)- and (S)-piperazic acids, components of naturally occurring antibiotic cyclodepsipeptides, was achieved in 80% overall yield by the use of a proline-catalyzed asymmetric α-hydrazination as the key step.

(2R,3R)- and (2S,3S)-3-Hydroxyleucines, components of cyclodepsipeptides, papuamides and polyoxypeptins, were efficiently synthesized along with their diastereomers from the corresponding β-keto-α-amino acid ester through dynamic kinetic resolution using RuCl2(binap)-catalyzed hydrogenation.

(3S,4R)-3,4-Dimethyl-(S)-glutamine, a common component of cyclodepsipeptides, papuamide A and callipeltin A, was stereoselectively prepared from (S)-pyroglutamic acid. The stereostructure of natural dimethylglutamine was unambiguously confirmed to be (2S,3S,4R) by comparison of the CD and NMR spectra of the synthetic 3,4-dimethylpyroglutamic acid with the hydrolysate of callipeltin A.

Optically active ethano Troger's base with configurationally stable stereogenic nitrogens and an ethylene bridge was synthesized by reaction with 1,2-dibromoethane and subsequent resolution using (−)- and (+)-di- p -toluoyl-D-tartaric acids from commercially available (±)-Troger's base in one step.

The γ-azetidinyl-β-hydroxy-α-amino acid derivative 2, a key intermediate for the total synthesis of mugineic acid (1), was stereoselectively prepared from readily available (2R,3R)-epoxysuccinic acid (3).