AB INITIO STUDY OF DEHALOHYDROGENATION REACTION OF 2–HALO–2,3–DIHYDROPHOSPHININE
H. Shirani Il Beigi1, M. Nikbakht2, P. Ghanbar pour2
1Islamic Azad University, Najaf Abad, Isfahan, Iran 2Novel Drug Delivery Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran
Keywords: ab initio, NBO, NICS, 2-halo-2, 3-dihydrophosphinines
Abstract
Decomposition of 2-fluoro-2,3-dihydrophosphinine (1), 2-chloro-2,3-dihydrophosphinine (3), 2-bromo-2,3-dihydrophosphinine (5) to phosphinine was investigated using Molecular orbital and density functional theory. Study on the B3LYP/6-311+G** level of theory revealed that the required energy for the decomposition of compounds 1, 3 and 5 to phosphinine is 30.56, 28.23 and 24.03 kcal×mol–1, respectively. HF/6-311+G**//B3LYP/6-311+G** calculated barrier height for the decomposition of compound 1, 3 and 5 to phosphinine is 57.56, 37.26 and 30.77 kcal×mol–1, respectively. Also, MP2/6-311+G**//B3LYP/6-311+G** results indicated that the barrier height for the decomposition of compound 1, 3 and 5 to phosphinine is 46.59, 47.28 and 42.57 kcal×mol–1, respectively. Natural bond orbital (NBO) population analysis and nuclear independent chemical shift (NICS) results showed that, reactants are non-aromatic but products of elimination reaction are aromatic, C-H and C-X bonds are broken and H-X bond is appear.
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