eng Oriental Scientific Publishing Company Biomedical and Pharmacology Journal 0974-6242 2015-12-28 8 2 565 572 10.13005/bpj/799 3853 article Sayyed Mostafa Habibi-Khorassani 1 Mehdi Shahraki 1 Malek Taher Maghsoodlou 1 Eideh Mofarrah 1 Elham Mofarrah 2 Sayyed Rasul Mousavi 1 Department of Chemistry, University of Sistan and Baluchestan, P. O. Box 98135-674, Zahedan, Iran Department of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran The hindered internal rotations around the partial carbon-carbon double bond (MeO₂C↑=CPPh₃), nitrogen-carbon (N↑-C-CH) and carbon-carbon single (MeO₂C↑H-C-C=PPh₃) bonds within dimethyl-2-(6-Aza uracil 1-yl)-3-(triphenylphosphoranylidene) butandioate has been experimentally studied by the dynamic ¹H NMR spectroscopic in variable temperatures. The activation (∆H^‡, ∆S^‡, ∆G^‡) and kinetic (k_c, E_a.) parameters were calculated in a series of separate dynamic ¹H NMR spectra. The energy of activation parameters obtained from classic, Eyring and Arrhenius methods were also compared for carbon-carbon double, this compound. The results from Eyring and Arrhenius plots were in good agreement, however, they were different with the classic method. Rotation around the carbon-carbon single bond ∆G^‡ has low value than rotation around the carbon-carbon double bond and rotation around the carbon-carbon single bond. https://biomedpharmajournal.org/vol8no2/dynamic-1h-nmr-study-of-the-hindered-internal-rotation-in-a-particular-biological-phosphorus-ylide-involving-6-azauracil/ Dynamic ¹H NMR Activations Parameters Internal Rotations Ylide Isomerism