| 1. |
- Langer, Vratislav, 1949, et al.
(författare)
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2-(2-Oxazolin-2-yl)benzene-1,4-diol: X-ray and density functional theory studies
- 2007
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Ingår i: Acta Crystallographica Section C: Crystal Structure Communications. - 0108-2701 .- 1600-5759. ; 63:3, s. o187-o189
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Tidskriftsartikel (refereegranskat)abstract
- In the crystal structure of the title compound, C9H9NO3, there are strong intramolecular O-H...N and intermolecular O-H...O hydrogen bonds which, together with weak intermolecular C-H...O hydrogen bonds, lead to the formation of infinite chains of molecules. The calculated intermolecular hydrogen-bond energies are -11.3 and -2.7 kJ mol-1, respectively, showing the dominant role of the O-H...O hydrogen bonding. A natural bond orbital analysis revealed the electron contribution of the lone pairs of the oxazoline N and O atoms, and of the two hydroxy O atoms, to the order of the relevant bonds.
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| 2. |
- Langer, Vratislav, 1949, et al.
(författare)
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3-(4-Bromophenyl)-5-(4-dimethylaminophenyl)-1-phenyl-2-pyrazoline: X-ray and density functional theory (DFT) studies
- 2007
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Ingår i: Acta Crystallographica Section C: Crystal Structure Communications. - 0108-2701 .- 1600-5759. ; C63:6, s. o340-o342
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Tidskriftsartikel (refereegranskat)abstract
- In the crystal structure of the title compound, C23H22BrN3, a strong conjugation of the pyrazoline chromophore with the aromatic rings at positions 1 and 3 is observed, as well as a significant shift in the synclinal→synperiplanar direction. The absolute structure was unequivocally determined. In the absence of clasical hydrogen-bond donors, the structure is stabilized by weak C-H…π interactions. This paper also reports the electronic structure of the title compound using NBO (natural bond order) analysis. The contributions of lone pairs to the relevant bonds were revealed.
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| 3. |
- Langer, Vratislav, 1949, et al.
(författare)
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(E)-Methyl 2-anilinomethylene-3-oxobutanoate: X-ray and density functional theory studies
- 2007
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Ingår i: Acta Crystallographica Section C: Crystal Structure Communications. - 0108-2701 .- 1600-5759. ; C63:9, s. o552-o554
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Tidskriftsartikel (refereegranskat)abstract
- Molecules of the title compound, C12H13NO3, are not planar and are stabilized by electrostatic interactions, as the dipole moment of the molecule is 3.76 D. They are also stabilized by intramolecular hydrogen bonds of N...O and C...O types, and by a complicated network of weak intermolecular hydrogen bonds of the C...O type. This paper also reports the theoretical investigation of the hydrogen bonding and electronic structure of the title compound using natural bond orbital (NBO) analysis.
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