Asymmetric catalysis of homo-coupling of 3-substituted naphthylamine and hetero-coupling with 3-substituted naphthol leading to 3,3'-dimethyl-2,2'-diaminobinaphthyl and -2-amino-2'-hydroxybinaphthyl.

Optically active 3,3'-dimethyl-2,2'-diamino-1,1'-binaphthyl (DM-DABN) and 3,3'-dimethyl-2-amino-2'-hydroxybinaphthyl (DM-NOBIN) derivatives were synthesized by Cu-(-)-sparteine complex-catalyzed enantioselective homo- and hetero-coupling of 2-naphthylamine, respectively. The difference in enantioselectivity was observed by changing the concentration of oxygen.

Practical enantioselective synthesis of axially chiral biaryl diphosphonates and dicarboxylates by cationic rhodium(I)/Segphos-catalyzed double [2 + 2 + 2] cycloaddition.

A cationic rhodium(I)/Segphos complex catalyzes a [2 + 2 + 2] cycloaddition of internal 1,6-diynes with a phosphonate- or ester-substituted 1,3-butadiyne leading to C(2)-symmetric axially chiral biaryl diphosphonates or dicarboxylates, respectively, in high yields with outstanding ee's. The use of a phosphonate- or ester-substituted 1,3-butadiyne as a cycloaddition partner and Segphos as a ligand is crucial for the success of this transformation.

Asymmetric hydrogenation of aryl ketones mediated by a copper catalyst.

[reaction: see text] A novel asymmetric hydrogenation protocol using a copper catalyst is reported. A Cu(I) complex in the presence of nonracemic BDPP hydrogenates aryl ketones with moderate to high enantioselectivity.

Achiral benzophenone ligand-rhodium complex with chiral diamine activator for high enantiocontrol in asymmetric transfer hydrogenation.

The chirality of an achiral benzophenone-based rhodium complex can be controlled by chiral diamines to afford significantly high enantioselectivity in the catalytic asymmetric transfer hydrogenation of ketones (up to 99% ee, 99% yield).

Racemic but tropos (chirally flexible) BIPHEP ligands for Rh(I)-complexes: highly enantioselective ene-type cyclization of 1,6-enynes.

[reaction: see text] The tropos (chirally flexible) or atropos (chirally rigid) nature of BIPHEP-Rh complexes at room temperature critically depends on the amines complexed. The aliphatic DPEN complex is atropos, whereas the aromatic DABN complex is tropos. BIPHEP-Rh chirality can thus be controlled by DABN at room temperature.

Highly enantioselective spiro cyclization of 1,6-enynes catalyzed by cationic skewphos rhodium(I) complex.

A cationic rhodium(I) complex having a skewphos ligand is shown to be a highly enantioselective catalyst for asymmetric carbocyclization of 1,6-enynes with tri-substituted olefins to control quaternary stereogenic centers of spiro-rings.

Molecular design of DABNTf as a highly efficient resolving reagent for racemic Pd complex with Tropos biphenylphosphine (BIPHEP) ligand: circular dichroism (CD) spectra of enantiopure BIPHEP-Pd complex.

The racemic Pd complexes with chirally flexible (tropos) biphenylphosphine (BIPHEP) ligands can be resolved but transformed into the enantio- and diastereo-pure complex. The enantiopure metal complex of BIPHEP ligand is thus obtained through enantiomer-selective complexation of a racemic BIPHEP-Pd complex with enantiopure 1,1'-binaphthyl-2,2'-di(triflyl)amide, DABNTf. The differential CD spectra of the enantiopure BIPHEP-Pd complex is also reported.

Asymmetric deactivation of racemic BINAP-Ru(II) catalysts through complete enantiomer discrimination by dimethylbinaphthylamine: highly enantioselective hydrogenation of olefin and beta-keto ester.

[reaction: see text] 3,3'-Dimethyl-2,2'-diamino-1,1'-binaphthyl (DM-DABN) is designed as a "chiral poison" (deactivator) for complete enantiomer resolution of racemic BINAP-Ru(II) catalysts in a highly enantioselective hydrogenation of beta-keto ester and kinetic resolution of racemic 2-cyclohexen-1-ol.

Asymmetric activation of the Pd catalyst bearing the tropos biphenylphosphine (BIPHEP) ligand with the chiral diaminobinaphthyl (DABN) activator.

[reaction: see text] The enantio- and diastereomerically pure Pd complex of the tropos biphenylphosphine (BIPHEP) ligand is obtained through complexation of the enantiopure (R)-diaminobinaphthyl (DABN) with either enantiomer of the BIPHEP-Pd catalyst, followed by tropo-inversion of the less favorable (S)-BIPHEP-Pd/(R)-DABN diastereomer to the more favorable (R)-BIPHEP-Pd/(R)-DABN diastereomer. The enantiopure BIPHEP-Pd catalyst with DABN affords higher enantioselectivity and catalytic efficiency as an activated Lewis acid catalyst than the enantiopure BIPHEP-Pd catalyst without DABN.

Resolution of Pd catalyst with tropos biphenylphosphine (BIPHEP) ligand by DM-DABN: asymmetric catalysis by an enantiopure BIPHEP-Pd complex.

[reaction: see text] The racemic Pd complex with the chirally flexible (tropos) biphenylphosphine (BIPHEP) ligand can be resolved with enantiopure 3,3'-dimethyl-2,2'-diamino-1,1'-binaphthyl (DM-DABN) as a resolving agent at room temperature. The enantiopure BIPHEP-Pd complex is obtained from complexation with enantiopure DABN followed by tropo-inversion into the single BIPHEP-Pd diastereomer at 80 degrees C and protonation at 0 degrees C. The enantiopure BIPHEP-Pd complex can be used as an efficient Lewis acid catalyst for the Diels-Alder reaction at room temperature to give high enantioselectivity (82% ee, 60%).