ABSTRACT
An acetate bridged tetranuclear copper(II) complex, [Cu4L2(µ2-η1:η1-CH3COO)6(CH3OH)2] (1), and a chloride, phenolate and azide co-bridged tetranuclear copper(II) complex, [Cu4L2Cl2(µ-Cl)2(µ1,1-N3)2]2CH3OH (2), where L is the deprotonated form of the Schiff base 5-bromo-2-((2-(2-hydroxyethylamino)ethylimino)methyl)phenol (HL), have been synthesized and characterized by elemental analysis, IR and UV spectra, and single crystal X-ray diffraction. Single crystal X-ray analysis revealed that the Cu atoms in both complexes are in square pyramidal geometry. In complex 1, two [CuL] units and [Cu2(µ2-η1:η1-CH3COO)4] core are linked through two acetate ligands. In complex 2, [Cu2LCl(µ-Cl)] units are linked together by two end-on azido ligands. The Schiff base ligand coordinates to the Cu atoms through four N and O donor atoms. The molecules of both complexes are linked through hydrogen bonds to generate three dimensional networks. The catalytic property of the complexes for epoxidation reactions of some alkenes was studied using tert-butylhydroperoxide as the terminal oxidant under mild conditions in acetonitrile.
ABSTRACT
A new triphenylphosphine adduct of cyclopalladated ferrocenylpyridazine containing a chloride anion, 2a, has been synthesized from the reaction of the chloride-bridged palladacyclic dimer 1a with triphenylphosphine. The corresponding adducts 3a,b containing iodide anion have been readily prepared through anion exchange reactions of 2a,b with NaI in acetone. These complexes were characterized by elemental analysis, IR and 1H-NMR. Additionally, their crystal structures have been determined by X-ray diffraction and intermolecular C-H···X (Cl, Br, I) bonds were found in the crystals. The use of these palladacycles as catalysts for the Suzuki and Sonogashira reactions was examined. The complexes 2a,b exhibited higher catalytic activity than the corresponding 3a,b in the Suzuki reaction. However, the order of activity of adducts with varying halogen anions is 3a~3b > 2a~>2b in the Sonogashira reaction.
Subject(s)
Ferrous Compounds/chemistry , Macrocyclic Compounds/chemistry , Organophosphorus Compounds/chemistry , Palladium/chemistry , Bromides/chemistry , Catalysis , Chlorides/chemistry , Crystallography, X-Ray , Magnetic Resonance Spectroscopy , MetallocenesABSTRACT
The asymmetric unit of the title compound, [Hg(C(13)H(10)N(3)O(2))Cl]·H(2)O, contains two independent mercury(II) complexes with slightly different conformations, related via a pseudo-inversion centre, and two water mol-ecules. The Hg(II) atoms show a typical linear geometry to a C atom of the benzene ring and to a Cl atom. A benzene C and the azomethine N atom chelate the Hg(II) atoms with weak intra-molecular Hgâ¯N bonding distances of 2.735â (3) and 2.739â (3)â Å, respectively. The resulting five-membered metallacycles are nearly coplanar with the benzene rings [dihedral angles = 0.9â (1) and 0.7â (1)°], while the pyridine rings make dihedral angles with the benzene units of 58.17â (1) and 56.58â (1)°. In the crystal structure, the Hg(II) complexes are linked by hydr-oxy donor and pyridine acceptor groups into chains along [010]. The water mol-ecules connect the complexes through inter-molecular O-Hâ¯O(carbon-yl) bonds in the a-axis direction, and the azomethine H atoms donate towards the water O atoms, forming a three-dimensional network of inter-molecular O-Hâ¯N, O-Hâ¯O and N-Hâ¯O hydrogen bonds.
ABSTRACT
In the title compound, C(20)H(15)N, the fluorene unit is essentially planar [r.m.s. deviation 0.0334â Å] and the benzene ring bound to the imine N atom bears a methyl group which is nearly coplanar [dihedral angle 0.5â (1)°]. The dihedral angle between the substituent benzene ring and the 9H-fluoren-9-imine unit is 71.1â (3)°. Inter-molecular π-π inter-actions between the benzene rings of adjacent fluorene units [centroid-centroid distance 3.8081â (13)â Å] are present in the crystal structure, resulting in a one-dimensional supra-molecular architecture.
