Novel neutral phosphinite bridged dinuclear ruthenium(II) arene complexes and their catalytic use in transfer hydrogenation of aromatic ketones: X-ray structure of a new Schiff base, N3,N3 '-di-2-hydroxybenzylidene-[2,2 ']bipyridinyl-3,3 '-diamine

Buldag, Ayseguel
Guemguem, Bahattin
Özkar, Saim
Yildirim, Leyla Tatar
A novel Schiff base N3,N3'-di-2-hydroxybenzylidene-[2,2']bipyridinyl-3,3'-diamine, 1 was synthesized from condensation of salicylaldehyde with 3,3'-diamino-2,2'-bipyridine. Reaction of 1 with two equivalents of PPh(2)Cl in the presence of Et(3)N proceeds in toluene to give N3,N3'-di-2-(diphenylphosphino)benzylidene-[2,2']bipyridinyl-3,3'-diamine, 2 in quantitative yield. Ruthenium(II) dimers [Ru(eta(6)-arene)(mu-Cl)]Cl](2) readily react with phosphinite ligand [(Ph(2)PO)(2)-C(24)H(16)N(4)], 2 in toluene at room temperature, to afford the neutral derivatives [C(24)H(16)N(4){OPPh(2)-Ru(eta(6)-arene)Cl(2}2)] {arene: benzene 3, p-cymene, 4}. All the complexes were fully characterized by analytical and spectroscopic methods. (31)P-{(1)H} NMR, (1)H-(13)C HETCOR or (1)H-(1)H COSY correlation experiments were used to confirm the spectral assignments. Molecular structure of the Schiff base, 1 was also determined by X-ray single crystal diffraction study. The catalytic activity of complexes 3 and 4 in the transfer hydrogenation of acetophenone derivatives was tested. Stable ruthenium(II)-phosphinite complexes were found to be efficient catalysts in the transfer hydrogenation of aromatic ketones in excellent conversions up to 99% (up to 530 per hour) in the presence of iso-PrOH/KOH.


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Novel mesostructured hybrid materials containing a molybdenum Schiff base complex grafted on the internal surface of SBA-15 pores were prepared by introducing MoO2(acac)(2) into a mesoporous silica functionalized with Schiff base ligands. The SBA-15 supports modified by an amine or salicylaldehyde were obtained by co-condensation of tetraethylorthosilicate and the corresponding organosilane in the presence of Pluronic P123 surfactant as a structure directing agent using bis[3-(trimethoxysilyl)propyl]amine o...
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In recent work we showed that Ziegler-type nanoparticles made from [Ir(1,5-COD)(mu-O2C8H15)](2) plus AlEt3 are an unusually thermally stable (>= 30 min at 200 degrees C), hydrocarbon-solvent soluble, high catalytic activity nanoparticle catalyst (I.K. Hamdemir, S. Ozkar, K.-H. Yih, J.E. Mondloch, R.G. Finke, ACS Catal. 2 (2012) 632-641). As such, they are analogous to-and currently the cleanest and best characterized model system for-Ziegler-type nanoparticles made from Co or Ni precatalysts plus AlEt3 whic...
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Ruthenium(0) nanoparticles supported on xonotlite nanowire (Ru(0)/X-NW) were prepared by the ion exchange of Rua* ions with Ca2+ ions in the lattice of xonotlite nanowire followed by their reduction with sodium borohydride in aqueous solution at room temperature. Ru(0)/X-NW show high catalytic activity and long life time in hydrogen generation from the hydrolysis of sodium borohydride with a turnover frequency value up to 305 min(-1) and a total turnover number of 63,100 mol H-2/mol Ru in hydrogen generatio...
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The asymmetric synthesis of cis-1,4-amino alcohols with a norbornene backbone was performed starting with (2S,3R)(-)-cis-hemiester 2 (98% ee). Chemoselective amination with NH4OH and HMPTA followed by LAH reduction afforded 5 and 7. respectively. Amido ester 6 was transformed into chiral ligand 9 with Grignard reaction followed by LAH reduction. The chiral ligands 5. 7. and 9 were subjected to asymmetric diethylzinc addition to examine their effectiveness as chiral catalysts. Among these, c chiral ligand 7 ...
Enantioselective synthesis of both enantiomers of 2-amino-2-(2-furyl)ethan-1-ol as a flexible building block for the preparation of serine and azasugars
Demir, Ayhan Sıtkı; Sesenoglu, O; Aksoy-Cam, H; Kaya, H; Aydogan, K (Elsevier BV, 2003-05-16)
The selective conversion of 1-(2-furyl)-2-hydroxyethan-1-one and ethyl 2-(2-furyl)-2-oxo acetate into (E)- and (Z)-oximes and oxime ethers followed by oxazaborolidine-catalyzed enantioselective reduction using different amino alcohols furnished both enantiomers of the important chiral building block 2-amino-2-(2-furyl)ethan-1-ol with an ee of up to 96%.
Citation Formats
M. AYDEMİR et al., “Novel neutral phosphinite bridged dinuclear ruthenium(II) arene complexes and their catalytic use in transfer hydrogenation of aromatic ketones: X-ray structure of a new Schiff base, N3,N3 ‘-di-2-hydroxybenzylidene-[2,2 ‘]bipyridinyl-3,3 ’-diamine,” JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL, pp. 75–81, 2010, Accessed: 00, 2020. [Online]. Available: