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    Direct arylation of heteroarenes by PEPPSI-type palladium-NHC complexes and representative quantum chemical calculations for the compound which the structure was determined by X-ray crystallography
    (Taylor & Francis Ltd, 2019) Sahin, Neslihan; Serdaroglu, Goncagul; Dusunceli, Serpil Demir; Tahir, Muhammad Navaz; Arici, Cengiz; Ozdemir, Ismail
    In this study, we synthesized five new PEPPSI-type Pd-NHC complexes with high yields around 78-83%. The structures of all complexes were characterized by FT-IR, H-1 NMR, and C-13{H-1} NMR spectroscopies. Further, the structure of 2c was determined by X-ray crystallography. The single-crystal structure of 2c shows that coordination geometry around Pd is distorted square planar. The Pd-NHC complexes were efficient catalysts for the direct C5-arylation of 2-n-butylthiazole, 2-n-butylfuran, and 2-n-butylthiophene with various aryl-bromides and showed high catalytic activity for arylation reaction using only 1 mol% catalyst loading at 130 degrees C for 1 h. The conversions for substrates containing electron-withdrawing groups were higher than for substituents containing electron-donating groups. In order to evaluate the catalytic activity of the complexes, representative electronic and spectroscopic simulations by DFT method have been performed for 2c. NBO analysis has revealed that the strongest interaction contributing to the lowering of the molecular stabilization energy for 2c is predicted as pi(C11-N27) -> pi*(N26-C28) with E-(2) = 73.93 kcal mol(-1). In addition, FMO analysis has implied that 2c is more chemically reactive because of its lower energy gap value. According to the other quantum chemical parameters, 2c is softer, better electrophile and has more charge-transfer capability than 1c.
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    PEPPSI type complexes: Synthesis, x-ray structures, spectral studies, molecular docking and theoretical investigations
    (Pergamon-Elsevier Science Ltd, 2021) Serdaroglu, Goncagul; Sahin, Neslihan; Ustun, Elvan; Tahir, Muhammad Navaz; Arici, Cengiz; Gurbuz, Nevin; Ozdemir, Ismail
    In this work, three novel potent benzimidazolium-derived PEPPSI type palladium complexes, namely dichloro[1-allyl-3-benzylbenzimidazole-2-ylidene]pyridine palladium(II) (1), dichloro[1-allyl-3-(1-naphthylmethyl)benzimidazole-2-ylidene]pyridine palladium(II) (2) and dichloro[1-allyl-3-(9-anthrylmethyl)benzimidazole-2-ylidene]pyridine palladium(II) (3), were synthesized and characterized by single X-ray crystallography, FT-IR and NMR spectroscopy. The results were compared with the relevant calculated data. After structural and spectroscopic determination, the performance of the global reactivity behavior of these derivatives was evaluated by quantum chemical parameters (QCP) obtained from DFT/B3LYP and HF methods utilized with the 6-311 g**/LANL2DZ basis set. Next, NBO analyses were conducted to enlighten the possible interactions that occur for each derivative and this revealed that the main role in the lowering of the stabilization energies of all the derivatives was sourced from n -> pi* and pi -> pi* interactions. Finally, all the complexes were analyzed for their anticancer potential by the molecular docking method with VEGFR (vascular endothelial growth factor receptor), thioredoxin reductase, breast cancer and the dodecamer structure of DNA. (C) 2021 Elsevier Ltd. All rights reserved.