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Abstract: A new family of achiral 3,3′,5,5′-tetrasubstituted-2,2′,6,6′-tetrahydroxy biphenyl ligand 4 was developed. The axial chirality of the ligand could be induced by the chelation of 2,2′,6,6′-tetrahydroxy groups with (R)-BINOL-Ti(O i Pr)2 to form an axially chiral bimetallic titanium catalyst 9. Compared with (R)-BINOL-Ti(O i Pr)2 catalyst, this novel catalyst 9 exhibited excellent activity and enantioselectivity for the carbonyl-ene reaction of methylstyrene and ethyl glyoxylate. 3,3′,5,5′-Tetrasubstituted groups showed a remarkable effect on both enantioselectivity and yield. With 9d prepared from 3,3′,5,5′-tetramethyl-2,2′,6,6′-tetrahydroxy biphenyl 4d as the catalyst, the best result, up to 97.6% ee and 99% yield, was obtained. Additionally, the bimetallic catalyst 9 also showed better catalytic capability than the corresponding monometallic catalyst. [Copyright &y& Elsevier]

Abstract: The Cu(I)-catalyzed azide-alkyne cycloaddition reaction (CuAAC) has been used to synthesize an anthracene-based fluorescent compound that undergoes strong fluorescence quenching in the presence of Cu(II). Fluorescence studies indicate that the compound forms a 1:1 complex and can be used to quantitatively determine micromolar concentrations of Cu(II) in aqueous solution. [Copyright &y& Elsevier]

Abstract: The novel C 2-symmetric metallocene-based ligands with only planar chirality were synthesized easily and applied in palladium-catalyzed asymmetric allylic substitution with excellent enantioselectivity and high catalytic activity. When two ester groups on Cp rings of the metallocene were replaced by hydroxymethyl groups, opposite configuration of the product was obtained with high catalytic activity and excellent enantioselectivity. The opposite configuration of products was also obtained when the hydroxyl groups were protected as esters or ethers. These results might be attributed to the different configuration of the diphosphine ligands–Pd(II) complexes. [Copyright &y& Elsevier]

Abstract: An enamine can serve as a good nucleophile for palladium-catalyzed asymmetric allylic alkylation, avoiding the use of an unstablilized ketone enolate formed by strong bases. In the presence of a palladium complex of chiral metallocene-based phosphino-oxazoline ligands, the reaction was carried out smoothly with high catalytic activity and excellent enantioselectivity. Different distances between the two Cp rings of ferrocene and ruthenocene affected the catalytic behavior in the reaction. Furthermore, high catalytic activity and good enantioselectivity were also afforded by the ferrocene-based diphosphine ligands with only planar chirality. [Copyright &y& Elsevier]

Abstract: Novel air-stable C 2-symmetric tetrasubstituted ruthenocene-based ligands were readily synthesized and used for palladium-catalyzed asymmetric allylic substitution showing excellent enantioselectivity and high catalytic activity. [Copyright &y& Elsevier]

Abstract: Highly efficient one-pot synthesis of 1,2,3-triazole-linked glycoconjugates was presented involving a Cu(I) catalyzed 1,3-dipolar cycloaddition as the key step. It offers a convenient route to prepare neoglycoconjugates derived from unprotected saccharides or peracetylated saccharides. [Copyright &y& Elsevier]

A Ni(II)-catalyzed asymmetric addition of alkenylboronic acids to aldimines has been developed employing a mono-RuPHOX ligand. A series of cyclic aldimines and alkenylboronic acids are tolerated under our catalytic system, giving various chiral allylamines in good yields and ees. [ABSTRACT FROM AUTHOR]

Abstract: Atropos phosphoramidites with the D 2-symmetric biphenyl backbone were diastereoselectively prepared with ease from achiral tetrahydroxy biphenyls. This type of ligands is proved to be highly efficient in the Cu-catalyzed conjugate additions of diethylzinc to α,β-unsaturated ketones and nitroalkenes. The unique D 2-symmetric backbone endows the ligands with an excellent chiral environment. [Copyright &y& Elsevier]

Abstract: Novel C 2-symmetric bisoxazoline ligands 5 with a ferrocene backbone and a hydroxyl group at the substituent of the oxazoline ring were designed and prepared. With these ligands, up to 94% ee was obtained for the alkylation of arylaldehyde with diethylzinc. [Copyright &y& Elsevier]

Abstract: Novel C 2-symmetric chiral bisoxazoline ligands with a bipyridinyl backbone were prepared with ease from 3,3′-dicarbomethoxy-2,2′-bipyridine and enantiomerically pure 2-amino alcohols via a corresponding amide as intermediate. Interestingly, when these ligands were coordinated with Pd(II) and Cu(I), different complexation behaviors were found. [Copyright &y& Elsevier]

Abstract: A new one-pot approach for the synthesis of aryl α-keto ester based on the diazo transfer and oxidation of diazo group is developed. [Copyright &y& Elsevier]