Ph. D. THESIS 2009

H2 … N3 = 1.839 Å H5 … N6 = 1.838 Å
H3 … N1 = 1.838 Å H6 … N4 = 1.835 Å
N1 … N2 = 3.496 Å N4 … N5 = 3.495 Å
N2 … N3 = 3.496 Å N5 … N6 = 3.492 Å
N3 … N1 = 3.488 Å N6 … N4 = 3.491 Å
O1 … O2 = 3.794 Å O4 … O5 = 3.794 Å
O2 … O3 = 3.793 Å O5 … O6 = 3.790 Å
O3 … O1 = 3.795 Å O6 … O4 = 3.793 Å
N1 … N4 = 3.735 Å
N2 … N5 = 3.730 Å
N3 … N6 = 3.734 Å
V molec = 1766.78 Å 3
For the anti isomer the energy modifications brought by the formation of
the cyclic dimer (Δ=G° = 30.43 kcal / mol; Δ=E°/dioxime molecule = 15.21
kcal / mol) and of the cyclic trimer were also calculated (Δ=G° = 54.57 kcal /
mol; Δ=E°/dioxime molecule = 18.19 kcal / mol). The calculated distances
from the H atoms of the OH groups to the N atoms of the partner molecules are
d = 1.928 Å for the dimer, and they cover the range d = 1.803-1.897 Å for the
trimer. Despite the higher calculated stability for the trimer of anti isomer, it
crystallizes in the dimer form, maybe due to the contribution of other packing
forces.
5-anti (dimer)
Intermolecular interaction energy: Δ=E AB = 30.43 kcal/mol (Δ=E AB/N molec = 15.22
kcal/mol)
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