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    Catalysts for the asymmetric transfer hydrogenation of various ketones from [3-[(2S)-2-[(diphenylphosphanyl)oxy]-3-phenoxypropyl]-1-methyl-1H-imidazol-3-ium chloride] and [Ru(?6-arene)(?-Cl)Cl]2, Ir(?5-C5Me5)(?-Cl)Cl]2 or [Rh(?-Cl)(cod)]2
    (Elsevier Science Sa, 2019) Meric, Nermin; Arslan, Nevin; Kayan, Cezmi; Rafikov, Khadichakhan; Zazybin, Alexey; Kerimkulova, Aygul; Aydemir, Murat
    The combination of [3-[(2S)-2-[(diphenylphosphanyl)oxy]-3-phenoxypropyl]-1-methyl-1H-imidazol-3-ium chloride] with [Ru(eta(6)-arene)(mu-Cl)Cl](2), Ir(eta(5)-C5Me5)(mu-Cl)Cl](2) or [Rh(mu-Cl)(cod)](2), in the presence of KOH/isoPrOH, has been found to generate catalysts that are capable of enantioselectively reducing alkyl, aryl ketones to the corresponding (R)-alcohols. Under optimized conditions, when the catalysts were applied to the asymmetric transfer hydrogenation, we obtained the secondary alcohol products in high conversions and enantioselectivities using only 0.5 mol% catalyst loading. In addition, [3-[(2S)-2-{[(chloro(eta(4)-1,5-cyclooctadiene)rhodium)diphenyl phosphanyl] oxy}-3-phenoxypropyl]-1-methyl-1H-imidazol-3-ium chloride], (6) complex is much more active than the other analogous complexes in the transfer hydrogenation. Catalyst 6 acts as excellent catalysts, giving the corresponding (R)-1-phenyl ethanol in 99% conversion in 30 min (TOF <= 396 h(-1)) and in high enantioselectivity (92% ee).
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    Deep eutectic solvents for sustainable management of asphaltene deposition in oil production
    (Engineered Science Publisher, 2024) Ryspaeva, Salimat; Kerimkulova, Aygul; Rafikova, Khadichakhan; Nauryzova, Saule; Islam, Sholpan; Aydemir, Murat; Kozhaisakova, Madina
    Deep Eutectic Solvents (DES) offer a sustainable solution to mitigating asphaltene deposition in oil production, minimizing environmental impact and enhancing the operational efficiency in the petroleum industry. The paper investigates the sustainable management of asphaltene deposition in oil production through the application of Deep Eutectic Solvents (DESs). Three DES formulations were prepared: DES1 (Citric acid:Glycerin, 1:4 ratio), DES2 (Citric acid:Ethylene Glycol, 1:4 ratio), and DES3 (Choline chloride:Glycerin, 1:2 ratio). The physical properties (pH, density, and viscosity) of these DESs were measured. The study utilized Karazhanbas crude oil from Western Kazakhstan, characterized by distinct hydrocarbon groups. The weight composition was as follows: Paraffin-naphthenic 17.2%, Aromatic (light) 10.2%, Aromatic (medium) 8.1%, Aromatic (heavy) 28.2%, Total resins 24.1%, and Asphaltenes 12.2%. The FTIR spectrum of the received DES and asphaltene was also determined. Asphaltene deposition was studied both with and without DES inhibitors. Microscopic tests revealed that DES3 exhibited superior results, as evidenced by significantly smaller asphaltene particle sizes compared to other DES formulations and the control without DES. The findings suggest that DES3 holds promise as an effective inhibitor for asphaltene deposition in oil production, offering a sustainable and environmentally friendly approach to address challenges associated with asphaltene-related issues in the petroleum industry.
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    Half-sandwich ruthenium(II) and iridium(III) complexes of imidazole based phosphinite ligands: antioxidant and antibacterial activities as well as electrochemical properties
    (Wiley-V C H Verlag Gmbh, 2024) Isik, Ugur; Rafikova, Khadichakhan; Meric, Nermin; Guzel, Remziye; Kerimkulova, Aygul; Akimbek, Arailym; Okumus, Veysi
    Ruthenium(II) and iridium(III) complexes of phosphinites including imidazole moiety were synthesized and characterized by microanalysis, IR, MS, and NMR spectroscopies. Antibacterial activity against Gram-positive and Gram-negative bacterial strains was assessed in all complexes. The highest radical scavenging (72.2 %) was obtained for [3-(3-chloro-2-({[dichloro(eta 6-benzene)ruthenium]diphenylphosphanyl}oxy)propyl)-1-butyl-1H-imidazol-3-ium chloride], 4 at 200 mu g/mL concentration, while [3-(3-chloro-2-({[dichloro(eta 5-pentamethylcyclopentadienyl)-iridium]diphenylphosphanyl}oxy)pro-pyl)-1-butyl-1H-imidazol-3-ium chloride], 6 demonstrated the highest antibacterial activity as 13 mm inhibition zone against E. hirea. Furthermore, optical and electrochemical featured of metal complexes containing imidazole phosphinite were investigated utilizing UV-vis absorption and cyclic voltammetry techniques. Consequently, all complexes can be proposed as metal-based charge convertible phosphinite complexes which may be employed as new generation and synergistic Dye-Sensitized Solar Cell (DSSC) materials. Ruthenium(II) and iridium(III) complexes of phosphinites including imidazole moiety are synthesized and characterized by microanalysis, IR, MS, and NMR spectroscopies. Their antibacterial activity against Gram-positive and Gram-negative bacterial strains is assessed. Furthermore, optical and electrochemical features of the metal complexes are investigated utilizing UV-vis absorption and cyclic voltammetry techniques. image