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A new class of chiral ferrocenyl diphosphine ligands with an imidazole ring, (Rc,SFc)-ImiFerroPhos, has been prepared from acylferrocenes through a five-step transformation and successfully applied in the Rh-catalyzed asymmetric hydrogenation of various 3-aryl-substituted 2-phosphonomethylpropenoates, in which a series of chiral 3-phosphono-2-arylmethylpropanoic acid derivatives were achieved in ee values of up to 98%. [ABSTRACT FROM AUTHOR]

A new class of unsymmetrical hybrid phosphine-aminophosphine ligands has been prepared from commercially available, inexpensive (S)-1-phenylethylamine through a concise synthetic procedure. These ligands are not very sensitive to air and moisture, and displayed good enantioselectivities in the Rh-catalyzed asymmetric hydrogenation of various dimethyl α-benzoyloxyethenephosphonates bearing β-aryl, β-alkyl, and β-alkoxy substituents and N-benzyloxycarbonyl α-enamido phosphonates, in which up to 97% ee was obtained. A side-by-side comparison study disclosed that these new phosphine-aminophosphine ligands showed better enantioselectivity than BoPhoz ligands. [ABSTRACT FROM AUTHOR]

An enantioselective synthesis of optically active 1-aryl or 1-alkyl substituted ethyiphosphonates, based on the first Rh- catalyzed asymmetric hydrogenation of corresponding α,β-unsaturated precursors with a P-stereogenic BoPhoz-type ligand under the mild condition, was developed, in which a wide range of 1-aryl or 1-alkyl substituted ethyiphosphonates were achieved in up to 98% ee. [ABSTRACT FROM AUTHOR]

The title compound, [Co(C12H8N2)(H2O)4]2(C10H2O8), consists of discrete tetra­aqua­(1,10-phenanthroline)cobalt(II) cations and 1,2,4,5-benzene­tetra­carboxyl­ate anions. The CoII atom is octa­hedrally coordinated by two N atoms of the 1,10-phenanthroline ligand and four O atoms of water mol­ecules. The anion lies on an inversion centre. A two-dimensional hydrogen-bonding network is formed by O atoms of benzene­tetra­carboxyl­ate and the coordinated water mol­ecules. [ABSTRACT FROM AUTHOR]

The title compound, [Dy2 (C8H7O2)6 (C12H8N2)2, forms binuclear complexes, viz. di-μ-4-methylbenzoato-Κ4O:O′-bis[bis- (4-methylbenzoato-Κ²O,O′)(1,10-phenanthroline-Κ² N,N′)-dysprosium(III)] tetra-μ-4-methylbenzoato-Κ8O:O′-bis[(4- methylbenzoato-Κ²O,O′)(1,10-phenanthroline-Κ² N,N′)dys- prosium(III)]. There are two independent binuclear complexes in the asymmetric unit, both of which are centrosym- metric. In one, the DyIII ions are linked by two bridging 4-methylbenzoate groups, while in the other, the DyIII ions are linked by four bridging 4-methylbenzoate groups. The remaining 4-methylbenzoate groups and 1,10-phenanthroline units coordinate to just one metal ion in bidentate modes. [ABSTRACT FROM AUTHOR]

A new family of chiral ferrocenyl P,S-ligands has been developed and successfully applied in a highly endo-selective catalytic asymmetric cycloaddition of azomethine ylides with various enones, including cyclic and acyclic α-enones. For cyclic α-enones, a [Cu(CH3CN)4]ClO4/(Rc,SFc)-2fcomplex catalyzed the cycloaddition to give the sole endo-cycloadducts in perfect enantioselectivities (normally 99% ee), while an AgOAc/(Rc,SFc)-2fcatalytic system exhibited good endo/exoselectivities (endo/exo= 91/9 to 96/4) and high enantiocontrol (up to 98% ee) for acyclic α-enones. [ABSTRACT FROM AUTHOR]

An enantioselective synthesis of chiral alkylphosphonates bearing a β-stereogenic center, based on the Rh-catalyzed asymmetric hydrogenation of corresponding β-substituted β,γ-unsaturated phosphonates with a ferrocenebased monophosphoramidite ligand under the mild hydrogenation conditions, was developed, in which an ee value of up to 98% was obtained. [ABSTRACT FROM AUTHOR]

A series of chiral -aryl--amino acid ester derivatives were synthesized in high enantioselectivities (93−97% ee) via the Rh-catalyzed asymmetric hydrogenation of -phthalimido-,-unsaturated carboxylic acid esters using highly modular chiral BoPhoz-type phosphine−aminophosphine ligands. The method has been applied successfully to the synthesis of several chiral pharmaceuticals including (R)-baclofen and (R)-rolipram with high enantioselectivities. [ABSTRACT FROM AUTHOR]

A series of chiral β-aryl-substituted γ-amino butyric acid derivatives were synthesized in good enantioselectivities via the Cu-catalyzed asymmetric conjugate reduction of γ-phthalimido-α,β-unsaturated carboxylic acid esters using Cu(OAc)2·H2O as a catalyst precursor, (S)-BINAP as a ligand, PMHS as a hydride source, and t-BuOH as an additive. The methodology has been applied successfully to the enantioselective synthesis of a chiral pharmaceutical, (R)-baclofen. [ABSTRACT FROM AUTHOR]

A series of BoPhoz-type ligands were successfully applied in the rhodium-catalyzed asymmetric hydrogenation of a number of β-substituted or unsubstituted α-(phthalimidomethyl)acrylates, affording good to excellent enantioselectivities. The results suggested that the presence of an N-H proton in the BoPhoz backbone could significantly improve the enantioselectivity, and ligand (Sc,Rp)-1d, bearing two CF3-groups in the 3,5-position of the phenyl ring of aminophosphino moiety, showed the highest enantioselectivity. [ABSTRACT FROM AUTHOR]

A new one-dimensional coordination polymer, catena-poly­[[aqua­(nitrato-κ2 O,O′)copper(II)]-μ-pyrazine-2-carboxyl­ato- κ3 N1, O:N4], [Cu(C5H3N2O2)(NO3)(H2O)] n, has been synthesized and characterized. The coordination environment of the copper(II) ion is distorted octahedral, arising from an N, O-bidentate 2-pyrazine­carboxyl­ate ligand, an N atom from a symmetry-related 2-pyrazine­carboxyl­ate ligand, a bidentate nitrate group and a water mol­ecule. The chains interact by way of O—H⋯O hydrogen bonds and C—H⋯O interactions. [ABSTRACT FROM AUTHOR]

The coordination environment of copper(II) in the title compound, [Cu(C6H4NO3)(NO3)(C12H8N2)], is square pyramidal; the basal plane comprises the two N atoms of 1,10-phenanthroline and the two O atoms of picolinate N-oxide, with the apical position occupied by a nitrate O atom. [ABSTRACT FROM AUTHOR]