2-Phenallyl was found to be a versatile protecting group of primary amines for the asymmetric one-pot three-component synthesis of propargylamines which leads to enantiomeric excess of up to 96%; it can be easily removed with a palladium(0)-catalyzed allylic substitution using 1,3-dimethylbarbituric acid as a nucleophile.

[reaction: see text] Reaction of various N-enoyl oxazolidinones 5a-f with N-aminophthalimide and lead tetraacetate in the presence of camphor-derived chiral ligands provides the desired N-phthalimidoaziridines 6a-f in good to high enantiomeric excess (67-95% ee) at 0 degrees C within 15 min. The absolute stereochemistry of the corresponding aziridine derivatives was established by chemical corr...

The LFA-1 inhibitor and leukocyte adhesion suppressor BIRT-377 was prepared in high enantiomeric excess by desymmetrization of dimethyl 2-p-bromobenzyl-2-methylmalonate, followed by condensation of the resulting carboxylic acid with 3,5-dichloroaniline, saponification of the remaining ester and Curtius rearrangement as the key steps. When Curtius rearrangement preceded the condensation step, (e...

We have developed a direct, asymmetric Michael reaction that can be performed in brine or seawater without addition of organic solvents. A bifunctional catalyst with long hydrophobic alkyl chains efficiently catalyzed Michael reactions and afforded the desired products in excellent yield with high enantiomeric excess, even when only an equal molar ratio of the donor to acceptor was used.

In an optically active liquid the diffraction angle depends on the circular polarization state of the incident light beam. We report the observation of circular differential diffraction in an isotropic chiral medium, and we demonstrate that double diffraction is an alternate means to determine the handedness (enantiomeric excess) of a solution.

A catalytic, enantioselective decarboxylative allylic alkylation of 4-thiopyranones is reported. The α-quaternary 4-thiopyranones produced are challenging to access by standard enolate alkylation owing to facile ring-opening β-sulfur elimination. In addition, reduction of the carbon-sulfur bonds provides access to elusive acyclic α-quaternary ketones. The alkylated products are obtained in up t...

Monoclonal antibodies have been elicited against an achiral rhodium complex and this complex was used in the presence of a resultant antibody, 1G8, for the catalytic hydrogenation of 2-acetamidoacrylic acid to produce N-acetyl-L-alanine in high (>98%) enantiomeric excess.

An enantioselective Brønsted acid catalyzed Mannich reaction between acetophenone derived enamines and N-Boc imines has been developed. Simple diol (S)-H(8)-BINOL has been identified as the optimal catalyst, to afford versatile beta-amino aryl ketones in good yield and enantiomeric excess.

Synthesis of both enantiomers of δ-unsaturated γ-amino acids via the enantiodivergent [3,3]-sigmatropic rearrangement strategy is reported. Excellent enantiomeric excess > 94% are observed in the strategy. Cell permeability of a fluorescent amino acid derivative is evaluated by live-cell imaging.

Enantioselective intramolecular conjugate addition reactions of short-lived C-O axially chiral enolates have been developed. The reactions proceeded with inversion of the configuration and provided dihydrobenzofurans with contiguous tetra- and trisubstituted carbon centers in up to 96% enantiomeric excess (ee).