Osman Serindağ

Catalytic Synthesis of 2-Methyl-1,4-Naphthoquinone (Vitamin K3) Over Silica-Supported Aminomethyl Phosphine-Ru(II), Pd(II), and Co(II) Complexes

Ru(II), Pd(II), and Co(II) complexes of the free ditertiary aminomethylphosphine ligand, N,N-bis(diphenylphosphinomethyl)aminopropyltriethoxysilane [(EtO)3Si(CH2)3 N(CH2PPh2)2] (DIPAPTES), and its SiO2-DIPAPES have been synthesized under a nitrogen atmosphere using Schlenk techniques. All the complexes were used as catalysts for the oxidation of 2-methyl naphthalene (2MN) to give 2-methyl-1,4-naphthoquinone (vitamin K3, menadione, 2MNQ) in the presence of hydrogen peroxide as a clean and cheap oxidant. The catalytic synthesis of vitamin K3 was investigated using both homogeneous catalysis with free complexes and heterogeneous catalysis with silica-supported complexes. [(DIPAPTES)PdCl2] and its silica-supported form showed the best catalytic activity for the selective oxidation of 2-methyl naphthalene to 2-methyl-1,4-naphtoquinone compared to the other metal complexes. 2MNQ yield reached 52.26% with the 2MN conversion of 90.52% using complex [(DIPAPTES)PdCl2] and 58.59% with the 2MN conversion of 99.56% using the silica supported [SiO2(DIPAPES)PdCl2] complex for 1 h. Recycling was investigated for the silica-supported Pd(II) complex and compared with the classical production of vitamin K3. Supplemental materials are available for this article. Go to the publishers online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.

Synthesis of some Platinum(II) Diphosphine Complexes of the Type [PtX2(P-P)] (X2 = CO3; X = CH3COO, CF3COO, NCO)

Abstract Treatment of aminobis(methylphosphine) complexes of platinum(II) with silver(I) salts in dichloromethane gives corresponding platinum(II) complexes of the type [PtX2(P-P)] where X2 = CO3; X= CH3COO, CF3COO, NCO; P-P = (Cy2PCH2)2NMe, dcpam; (Ph2PCH2)2NMe, dppam). The complexes have been characterised by using spectroscopic techniques such as 31P-{1H] and 1H NMR, IR, and mass spectrometry. Referee I: D. M Roddick Referee II: L. K. Woo

Hydrogenation of Acetophenone and Its Derivatives with 2-Propanol Using Aminomethylphosphine-Ruthenium Catalysis

The reaction of 3′-aminopropyltriethoxysilane with the phosphonium salt ([Ph2P(CH2OH)2]Cl) gives an aminomethylphosphine-type ligand ((CH3CH2O)3Si(CH2)3N(CH2PPh2)2). Reaction of the ligand ((CH3CH2O)3Si(CH2)3N(CH2PPh2)2) with silica gives silica supported aminomethylphosphine ligand (SiO2)-O-Si(CH2)3N(CH2PPh2)2). The ligands were refluxed with [RuCl2(p-cymene)]2 in toluene to give [RuCl2((CH3CH2O)3Si(CH2)3N(CH2PPh2)2)] and silica-supported SiO2)-O-[RuCl2((Si(CH2)3N(CH2PPh2)2)2] complex, respectively. The catalytic studies show that the complexes [RuCl2((CH3CH2O)3Si(CH2)3N(CH2PPh2)2)] and SiO2)-O-[RuCl2((CH3CH2O)3Si(CH2)3N(CH2PPh2)2)2] are very active catalysts for the transfer hydrogenation of acetophenone by 2-propanol in basic media. The best yield was observed in hydrogenation of m-methoxy acetophenone (95%) with catalyst [RuCl2((CH3CH2O)3Si(CH2)3N(CH2PPh2)2)].

Antioxidant Enzyme Inhibitor Role of Phosphine Metal Complexes in Lung and Leukemia Cell Lines

Phosphine metal complexes have been recently evaluated in the field of cancer therapy. In this research, the cytotoxic effects of some metal phosphines {[PdCl2((CH2OH)2PCH2)2NCH3] (C1), [RuCl2(((CH2OH)2PCH2)2NCH3)2] (C2), [PtCl2((Ph2PCH2)2NCH3)(timin)2] (C3)} on K562 (human myelogenous leukemia cell line) and A549 (adenocarcinomic human alveolar basal epithelial cells) cells were investigated using the MTT test. C1 and C2 are water-soluble metal complexes, which may have some advantages in in vitro and in vivo studies. The effects of the above-mentioned metal complexes on thioredoxin reductase (TrxR) (EC: 1.8.1.9), glutathione peroxidase (GPx) (EC: 1.11.1.9), and catalase (Cat) (EC: 1.11.1.6) enzymes were also tested. The results of this research showed that all three metal complexes indicated dose-dependent cytotoxicity on A549 and K562 cell lines and that the complexes inhibited different percentages of the TrxR, GPx, and Cat enzymes of these tumor cells.

Synthesis and Catalytic Activities of Copper(I) Complexes of Bis(diphenylphosphinomethyl)amino Ligand and its Silica-supported Form

Cu(I) complexes of free ditertiary aminomethylphosphine ligand, N,N-bis(diphenylphosphinomethyl)aminopropyltriethox- ysilane (DIPAPTES) and its silica supported form (SiO2-DIPAPES), have been synthesized under nitrogen atmosphere using Schlenk method and characterized by atomic absorption, FT-IR, NMR (1H and 31P), and elemental analysis. Acetylacetonate (acac)− complexes of Cr(III) and Mn(III) complexes were prepared according to the literature. All the complexes were used as catalysts for the oxidation of 2-methyl naphthalene (2MN) to 2-methyl-1,4-naphthoquinone (Vitamin K3, menadione, 2MNQ) using hydrogen peroxide as a clean and cheap oxidant. All the complexes did not show good catalytic activity for the selective oxidation of 2-methyl naphthalene to 2-methyl-1,4-naphthoquinone.

Synthesis and Characterization of Mono- and Dinuclear Metal Complexes with Novel Azo Compounds and their Dyeing Properties

The coupling reaction of 1-amino 4-(2′ -amino benzene sulfonic acid) 2-methyl anthraquinone, 1-amino 4-(p-(β -sulfatoetyl sulfonyl aniline) 2-methyl anthraquinone, 1-amino 4-(5′ -amino naphtaline-3′ -sulfonic acid) 2-methyl anthraquinone with 4-N-(4′,6′ -dichloro-s-triazine)-β -sulfatoetyl sulfonic acid and 5-N-(4′,6′ -dichloro-s-triazine)naphtaline-2-sulfonic acid in the presence of sodium hydroxide solution were maintained to give anthraquinone derivatives after the diazotization reactions. The metal complexes of these ligands that have dye character were prepared with Cr III , Co II and Fe III transition metal salts and their characterized by analytical and spectroscopic methods as mono and dinuclear complexes. Atomic absorption and magnetic susceptibility results showed that the complexes have octahedral geometry. The synthesized compounds were carried out for dyeing of cotton and wool fibers, which were observed the deeper colors according to their color space values. Their fastnesses such as washing, perspiration and light exhibited good qualities.

A quantum chemical investigation of electrophilic addition reaction of bromine to benzonorbornadiene

Abstract The molecular complexes formed by the treatment of bromine with benzonorbornodiene have been studied by the AM1 semiempirical method and their stable configurations and also stabilization energies have been determined. It has been found that the molecular complexes formed by the attack of bromine on the double bond of benzonorbornadiene, from the exo direction are more stable than those formed from the endo direction. Possible various cations and radical intermediates of the electrophilic addition reaction of bromine to benzonobornadiene have been investigated by MNDO and ab initio methods. The nonclassical delocalized bromocarbonium cation is the most stable among these cations according to both methods, and the ionic addition reaction occurs via this cation.

Pd(II) complexes of novel phosphine ligands: Synthesis, characterization, and catalytic activities on Heck reaction

GRAPHICAL ABSTRACT ABSTRACT Novel phosphine oxides, (((3-methylpyridin-2-yl)amino)methyl)diphenylphosphine oxide (1) and diphenyl((pyrazin-2-ylamino)methyl)phosphine oxide (2), were synthesized and characterized. Phosphines ligands (3 and 4) were obtained by the reduction of 1 and 2 with AlH3, monitored by 31P NMR spectroscopy. Pd(II) complexes of 3 and 4 were synthesized and characterized (5 and 6). The catalytic activity of 5 and 6 was tested on the reaction of styrene with both activated and deactivated aryl bromides in air. The results of the catalytic experiments were discussed through DFT calculations.

Synthesis of Some Nickel(II) Diphosphine Complexes Having Coordinated Carboxylates

Treatment of aminobis(methylphosphine) complexes of nickel(II) with carboxylic acids in the presence of silver(I) salts in dichloromethane gives the corresponding nickel(II) complexes of the type [NiA(P-P] where A = CO3 −− (carbonate), (2),2-− OC6H4CO2 − (salicylate, Sal), (3),−O2CCH2CH2 CH(NH2)CO2 − (glutamate, Glu), (4), −O2 CCH2CH2CO2 − (succinicate, Suc), (5); P-P = (Cy2PCH2)2NMe (dcpam), (Ph2PCH2)2NMe (dppam). The complexes have been characterized by spectroscopic techniques such as 31P-{1H} NMR, FT-IR, UV-Vis. and mass spectrometry.