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Fourteen new RuII -arene (p-cymene/benzene) complexes (C1-C14) have been synthesized by varying the N-terminal substituent in the furoylthiourea ligand and satisfactorily characterized by using analytical and spectroscopic techniques. Electrostatic potential maps predicted that the electronic effect of the substituents was mostly localized, with some influence seen on the labile chloride ligands. The structure-activity relationships of the Ru-p-cymene and Ru-benzene complexes showed opposite trends. All the complexes were found to be highly toxic towards IMR-32 cancer cells, with C5 (Ru-p-cymene complex containing C6 H2 (CH3 )3 as N-terminal substituent) and C13 (Ru-benzene complex containing C6 H4 (CF3 ) as N-terminal substituent) showing the highest activity among each set of complexes, and hence they were chosen for further study. These complexes showed different behavior in aqueous solutions, and were also found to catalytically oxidize glutathione. They also promoted cell death by apoptosis and cell cycle arrest. Furthermore, the complexes showed good binding ability with the receptors Pim-1 kinase and vascular endothelial growth factor receptor 2, commonly overexpressed in cancer cells.

2-[(E)-{(1S,2R)-1-hydroxy-1-phenylpropan-2-ylimino}methyl]phenol has been synthesized and its influence on corrosion of mild steel in 1 M HCl solution has been studied by means of weight loss and electrochemical measurements under various circumstances. The inhibitor showed a maximum of 91 % of inhibition efficiency at 100 ppm. Interestingly, the inhibition efficiency has decreased on increasing the inhibitor concentration. This abnormal behavior is attributed to the release of phenolic hydrogen from the molecule. The mechanism of corrosion inhibition follows Langmuir adsorption isotherm. The negative ∆G ads indicates the spontaneous adsorption of the inhibitor on mild steel surface. Potentiodynamic polarization studies show that it is a mixed type inhibitor with predominant cathodic inhibition. UV–Visible spectroscopy of the inhibitor and inhibitor adsorbed on the mild steel confirmed the chemical interaction of the inhibitor with the metal surface.

A series of 4-substituted N-(2-mercaptophenyl)salicylideneimine Schiff bases were synthesized and investigated for corrosion inhibition of mild steel in hydrochloric acid medium. Inhibition through adsorption mechanism is proposed for these inhibitors, which is well supported by electrochemical impedance spectroscopy, the Langmuir adsorption isotherm and Scanning Electron Microscope morphologies of inhibited and uninhibited mild steel specimens. The negative ∆Gads indicates the spontaneous adsorption of the inhibitor on a mild steel surface. Among all the examined inhibitors, 5-bromo-N-(2-mercaptophenyl)salicylideneimine showed a higher inhibition efficiency. In order to reveal the usefulness of these Schiff bases as corrosion inhibitors under various circumstances, weight loss measurements were performed at various temperatures, acid concentrations and immersion times.

A series of norephedrine-based Schiff bases (1a–6a and 1b–6b) were synthesized by reacting substituted salicylaldehydes with d-norephedrine or l-norephedrine. The structure of these compounds was confirmed by elemental analyses and spectroscopic techniques. The molecular structures of 5a and 6a have been determined by X-ray crystallography, which revealed that the compounds are in the oxoamino form, with bent intramolecular N-H···O (N···O ≈ 2.58 A) hydrogen bonds and that they are associated in dimers bridged by linear intermolecular O-H···O (O···O ≈ 2.69 A) hydrogen bonds. The density functional theory calculations on 5a confirmed that the oxoamino form is more stable than the phenolimino form by 12.2 kcal/mol. All the compounds were evaluated for their antibacterial activity using resazurin dye as indicator by twofold dilution method against four bacteria namely, Bacillus subtilis (NCIM2718), Staphylococcus aureus (NCIM5021), Escherichia coli (NCIM2931), and Proteus vulgaris (NCIM2813).

The synthesis and characterization of several hexa-coordinated ruthenium(III) complexes of the type [RuCl(PPh3)2(L)] (L = dibasic tridentate ligand derived by the condensation of salicylaldehyde/o-vanillin with o-aminophenol/o-aminothiophenol) are reported. IR, electronic, EPR spectral data and redox bahaviour of the complexes are discussed. An octahedral geometry has been tentatively proposed for all the complexes. The new complexes were found to be effective catalysts for the oxidation of benzyl alcohol and cyclohexanol to benzaldehyde and cyclohexanone respectively using N-methylmorpholine-N-oxide as a co-oxidant. Copyright © 2007 John Wiley & Sons, Ltd.

The synthesis and characterization of several hexa-coordinated ruthenium(III) Schiff base complexes of the type [RuX(EPh3)(L)] (X = Cl or Br; E = P or As; L = dianion of the tetradentate Schiff base) are reported. IR, EPR, electronic spectra and cyclic voltammetric data of the complexes are discussed. An octahedral geometry has been tentatively proposed for all of these complexes. The new complexes have been subjected to catalytic activity in the reaction of oxidation of alcohols in the presence of N-methylmorpholine-N-oxide. Copyright © 2007 John Wiley & Sons, Ltd.

The coupling of β-diketones succeeds using aryl chlorides, bromides and iodides, with selective activation of the bromide over chloride on case of dihalogenated compounds.

Both ruthenium catalysts show high catalytic activity towards transfer hydrogenation of carbonyl compounds using isopropanol as hydrogen donor as well as solvent.

Copper (Cu) based nanoparticles mediated organic transformations have been focused worldwide because these methodologies afford industrially important fine chemicals under mild conditions. Moreover, Cu is environment friendly and relatively inexpensive. This review highlights the important developments of Cu based nanocatalysts for organic transformations.

The novel title catalyst is successfully employed to the selective oxidation of primary and secondary alcohols with periodic acid.

C–O/C–S cross coupling of aryl halides with phenol or thiophenol was studied under ligand-free condition at room temperature over CuO nanocatalyst. The scope of the reaction was extended to various aryl halides and substituted phenols under optimized condition. In general, efficient, selective, and reusable heterogeneous nano CuO catalytic system has been developed for room temperature C–O and C–S Ullmann type cross coupling reactions.

Aromatic, cyclic and aliphatic amines can be treated with symmetric and asymmetric diketones and ketoesters to produce β-ketoenamines in good to excellent yields.

The catalyst is prepared and used for the title reaction of aromatic aldehydes with nitromethane.

Ruthenium acts as a good catalyst for the racemization reaction of secondary alcohols and amines. Ruthenium-catalyzed racemization is coupled with enzymatic kinetic resolution to prepare chiral compounds in 100% theoretical yield. Ten ruthenium complexes ( 1 – 10 ) act as a good catalyst the for racemization reaction and are also compatible with DKR process. Two other ruthenium complexes [RuCl 2 (PPh 3 ) 3 ] and [Cp ∗ RuCl(COD)] are active for racemization reaction but their successful compatibility with DKR has not yet been reported. Ru/γ-Al 2 O 3 and Ru–HAP are the heterogeneous catalysts used for the racemization reaction. They have also not been employed for DKR process. Polymer supported ruthenium is employed as a reusable racemization catalyst for aerobic DKR of alcohols.