Organic solutions of poly-γ-(benzyl-L-glutamate) (PBLG) generate a sufficient differential ordering effect (DOE) to discriminate enantiomers using proton decoupled carbon-13 NMR in natural abundance. Discrimination between enantiomers is observed through the carbon-13 chemical shift anisotropy (CSA) differences. This method is successfully applied to a large number of chiral molecules including...

We developed a novel (S)-L-phenylalanine derived-bidentate chiral diaminophosphine oxide (DIAPHOX) preligand (S,S(P))-9b, which was successfully applied to Pd-catalyzed asymmetric allylic alkylation and amination. Using the Pd-(S,S(P))-9b catalyst system, asymmetric allylic alkylation and amination proceeded very smoothly, affording the corresponding products in excellent yield with high enanti...

These enzyrnes are indisputably valuable but have certain disadvantages, among which is often imperfect enantioselectivity. The standards in enantioselective synthesis are now very high: for most applications, an enantiomeric excess (ee) in an enantioselective step of less than 90% is essentially useless, and values of ee >99% are very desirable.a It is often difficult to achieve broad substrat...

Single-handed PQXphos, i.e., helical poly(quinoxaline-2,3-diyl)s bearing diarylphosphino pendant groups, served as remarkable chiral ligands in palladium-catalyzed asymmetric hydrosilylation of styrenes and asymmetric biaryl synthesis by Suzuki–Miyaura coupling, affording up to 98 % enantiomeric excess (e.e.) in both reactions. A palladium complex of high-molecular-weight variant (1000mer) of P...

The techniques of combinatorial chemistry have recently been applied to the discovery of new asymmetric catalysts for a variety of organic transformations.1 These techniques are useful for increasing the efficiency by which chiral ligands for metal catalysts are discovered since the design of these ligands is largely an empirical process, and there are currently no simple rules for reliably pro...

Isotopic chirality influences sensitively the enantiomeric outcome of the Soai asymmetric autocatalysis. Therefore magnitude and eventual effects of isotopic chirality caused by natural abundance isotopic substitution (H, C, O, Zn) in the reagents of the Soai reaction were analyzed by combinatorics and probability calculations. Expectable enantiomeric excesses were calculated by the Pars–Mills ...

Chiral tertiary and quaternary amine solvating agents for NMR spectroscopy were synthesized from the wood resin derivative (+)-dehydroabietylamine (2). The resolution of enantiomers of model compounds [Mosher's acid (3) and its n-Bu₄N salt (4)] (guests) by (+)-dehydroabietyl-N,N-dimethylmethanamine (5) and its ten different ammonium salts (hosts) was studied. The best results with 3 were obtain...

Compounds a containing bicyclo[1.1.1]pentane (BCP) adjacent to chiral center can be prepared with high enantiomeric excess through asymmetric transfer hydrogenation (ATH) of ketones. In the reduction step, BCP occupies position distant from η6-arene catalyst. The was applied synthesis analogue antihistamine drug neobenodine.