J. Janczak, R. Kubiak / Journal of Molecular Structure 749 (2005) 60–69
69
´
[8] R. Kubiak, J. Janczak, M. Sledz, J. Mol. Struct. 610 (2002) 59.
´
The energy barrier at the 08 (or equivalent at 1808) of
w2.1 kJ/mol is smaller than the RT value of w2.5 kJ/mol
(at room temperature). Thus in absence of any specific
interactions (as present in the crystal), the oscillation
between the two global minima around the 08 (C21.1 and
K21.18) is possible at room temperature. Whereas the
energy barrier at 908 (or equivalent barrier at 2708) is greater
by a factor of w7 in relation to RT energy and the change of
the conformation from 21.18 to the 158.9 is hindered at room
temperature.
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Only one CbN group in o-dicyanobenzene undergoes
transformation in the presence of cyanoguanidine yielding
2-(20-cyanophenyl)-4,6-diamino-1,3,5-triazine in crystal-
line form. The interaction of the polar CbN group with
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5. Supplementary material
Additional material comprising full details of the
X-ray data collection and final refinement parameters
including anisotropic thermal parameters and full list of
the bond lengths and angles have been deposited with the
Cambridge Crystallographic Data Center in the CIF
format as supplementary publication No. CCDC 240726.
Copies of the data can be obtained free of charge on the
application to CCDC, 12 Union Road, Cambridge
CB21EZ, UK (Fax: C44 1223 336 033; e-mail:
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