Well Defined Phosphine Free Ni-Catalyzed Dehydrogenation of Secondary Alcohols for the Synthesis of Ketones and Ketazines.

In this work, we unveil a novel synthesis of bench stable Ni (II) complexes supported by tetradentate Schiff-base ligands and the complexes were devoid of any phosphine or phosphine-based ligand. These Ni-complexes were successfully applied for the dehydrogenation of secondary alcohols for ketone and ketazine syntheses. Secondary alcohols with different functional groups were well tolerated during catalytic cycle.

Bis(2-hy-droxy-2,3-di-hydro-1-inden-1-aminium) tetra-chlorido-palladate(II) hemihydrate.

A new square-planar palladium complex salt hydrate, (CHNO)[PdCl]·0.5HO, has been characterized. The asymmetric unit of the complex salt comprises two [PdCl] dianions, four 2-hy-droxy-2,3-di-hydro-1-inden-1-aminium cations, each derived from (1,2)-(+)-1-amino-indan-2-ol, and one water mol-ecule of crystallization.

Crystal structure of a phenoxyl radical complex relevant to the metal site of the galactose oxidase enzyme: A facile one-pot synthesis, evidence for hydrogen atom transfer and DNA cleavage self-activation.

Copper complexes [Cu(LH)ClO] (1) and [Cu(L)NO] (2), which are relevant to the metal site of the galactose oxidase enzyme, were synthesized and characterized by different spectroscopic methods. LH and LH [where LH stands for 2,2'-((1,1')(2,2'-(pyridine-2,6-diyl)bis(2-phenylhydrazin-2-yl-1-ylidene))bis(methanylylidene))diphenol and LH stands for 6,6'-((1,1')-(2,2'-(pyridine-2,6-diyl)bis(2-phenylhydrazin-2-yl-1-ylidene))bis(methanylylidene))bis(2,4-di--butylphenol), H stands for dissociable proton] are pentadentate ligands. These ligands provide pyridyl N, two imine N, and two non-innocent phenoxyl and phenolato O donors, forming complex 1 as a non-radical complex, while complex 2 is a phenoxyl radical complex.

Selective Formation of Mononuclear Palladium and Acetonitrile-Bridged Dinuclear Palladium Complexes Containing a Chiral Tridentate Ligand.

From the chiral Schiff base tridentate ligand , unusual acetonitrile-bridged dinuclear palladium complex and organopalladium complex were synthesized selectively by using acetonitrile and ethanol, respectively. The chiral tridentate Schiff base ligand was bound to the palladium metal center with different chelation modes ([ONO] for and [CNO] for ). Complex constitutes the first example of dinuclear metal complexes connected only by a bridging acetonitrile, in which an exceptionally short C≡N bond distance [0.

The design of synthetic superoxide dismutase mimetics: seven-coordinate water soluble manganese(ii) and iron(ii) complexes and their superoxide dismutase-like activity studies.

Bio-inspired manganese [Mn(NPy)(HO)(CHOH)](ClO) (1) and iron [Fe(NPy)(HO)(ClO)]ClO (2) complexes derived from a pentadentate ligand (NPy = 2,6-bis((E)-1-phenyl-2-(pyridin-2-ylmethylene)hydrazinyl)pyridine) framework containing a N binding motif were synthesized and characterized using different spectroscopic methods. The molecular structures of complexes 1 and 2 were determined by X-ray crystallography. These complexes were found to be stable under physiological conditions and exhibited an excellent superoxide dismutase (SOD) activity.

Mn(II) based T and T potential MRI contrast agent appended with tryptamine: Recognition moiety for Aβ-plaques.

We report the synthesis and characterization of manganese(II) complexes having pentadentate ligands L (2,6-bis(1-(2-phenyl-2-(pyridin-2-yl)hydrazono)ethyl)pyridine), L (methyl 2,6-bis((E)-1-(2-phenyl-2-(pyridin-2yl)hydrazono)ethyl)isonicotinate), L (N-(2-(1H-indol-3-yl)ethyl)-2,6-bis((E)-1-(2-phenyl-2-(pyridin2yl)hydrazono)ethyl)isonicotiamide) and their application as dual contrast agents for simultaneous T and T weighted magnetic resonance imaging. Single crystal analysis of all the complexes [MnL, MnL and MnL] confirm the formation of novel seven-coordinate manganese complexes with an inner sphere water and perchlorate ion. The Magnetic Resonance Imaging (MRI) contrast agent [MnL] was further modified by incorporating tryptamine as a binding moiety specific to Amyloid Beta-fibrils (Aβ-fibrils) in Alzhiemer's disease (AD) and it's in vitro evaluation for specific binding with Aβ-fibrils indicated as a bio-marker of AD.