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    Ferrocene based chiral binuclear η6-benzene-Ru(II)-phosphinite complexes: Synthesis, characterization and catalytic activity in asymmetric reduction of ketones
    (Wiley, 2018) Al-bayati, Yaser W. Abdlhmed; Karakaş, Duygu Elma; Meriç, Nermin; Aydemir, Murat; Durap, Feyyaz; Baysal, Akın; 0000-0001-7294-6792; 0000-0003-0899-1948; 0000-0003-2582-9993
    In the present study, a series of chiral C-2-symmetric ferrocenyl based binuclear (6)-benzene-Ru(II) complexes bearing diphenylphosphinite and diisopropylphosphinite moieties have been synthesised. The new binuclear (6)-benzene-Ru(II)-phosphinite complexes were characterised based on nuclear magnetic resonance (H-1, C-13, P-31-NMR), FT-IR spectroscopy and elemental analysis. Then, these complexes have been screened as catalytic precursors in the transfer hydrogenation of acetophenone with 2-propanol as both the hydrogen source and solvent in the presence of KOH. The corresponding optically active secondary alcohols were obtained in excellent conversion rates between 96 and 99% and moderate to good enantioselectivities (up to 78% ee). The complex 5 was the most efficient catalyst among the four new complexes investigated herein.
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    Integrated catalytic and energy storage performance of grass waste derived Ni-Based catalyst
    (Springer Nature, 2024) Karakaş, Duygu Elma; Horoz, Sabit; Durap, Feyyaz; Orak, Ceren; Kaya, Mustafa
    This study focuses on the optimization and characterization of a grass waste-derived catalyst, GW-Ni-Cat, for hydrogen generation via NaBH4 methanolysis, as well as its application in supercapacitors. Optimization experiments were conducted to determine the optimal conditions for acid concentration, metal concentration, carbonization temperature, and carbonization time. The catalyst was characterized using various techniques including FTIR, XRD, SEM, TEM, BET, and ICP-OES. Performance experiments demonstrated the catalyst's efficiency in hydrogen generation, with key factors such as catalyst amount, NaBH4 concentration, and temperature influencing the reaction kinetics. Reusability tests showed the catalyst's stability over multiple cycles. Electrochemical characterization revealed the suitability of GW-Ni-Cat as an electrode material for supercapacitors, with high specific capacitance values. Comparison with other bio-based supercapacitors demonstrated the superior performance of GW-Ni-Cat. Overall, this study presents GW-Ni-Cat as a versatile and efficient material for both hydrogen generation and energy storage applications.
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    Synthesis, characterization and first application of chiral C2-symmetric bis(phosphinite)-Pd(II) complexes as catalysts in asymmetric intermolecular Heck reactions
    (Wiley-Blackwell, 2016) Karakaş, Duygu Elma; Durap, Feyyaz; Aydemir, Murat; Baysal, Akın; 0000-0003-2582-9993; 0000-0001-7294-6792; 0000-0003-0899-1948
    A series of new chiral C-2-symmetric bis(phosphinite) ligands and their palladium(II) complexes have been synthesized and for the first time used as catalysts in the palladium-catalysed asymmetric intermolecular Heck coupling reactions of 2,3-dihydrofuran with iodobenzene or aryl triflate. Under optimized conditions, products were obtained with high conversions and moderate to good enantioselectivities. The new C-2-symmetric bis(phosphinite) ligands and their palladium(II) complexes were characterized using multinuclear NMR and Fourier transform infrared spectroscopies and elemental analysis. Copyright (c) 2015 John Wiley & Sons, Ltd.