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Published on: November 21, 2013
Three N2-benzoyloxybenzamidines: sheet structures built from hard and soft hydrogen bonds and aromatic pi-pi stacking
Carlos E M Carvalho1, Solange M S V Wardell, James L Wardell
1Instituto de Química, Universidade Federal Fluminense, 24020-150 Niterói, Rio de Janeiro, RJ, Brazil.
Abstract:
Molecules of the title compounds N(2)-(benzoyloxy)benzamidine, C(14)H(12)N(2)O(2), (I), N(2)-(2-hydroxybenzoyloxy)benzamidine, C(14)H(12)N(2)O(3), (II), and N(2)-benzoyloxy-2-hydroxybenzamidine, C(14)H(12)N(2)O(3), (III), all have extended chain conformations, with the aryl groups remote from one another. In (I), the molecules are linked into chains by a single N-H...N hydrogen bond [H...N = 2.15 A, N...N = 3.029 (2) A and N-H...N = 153 degrees ] and these chains are linked into sheets by means of aromatic pi-pi stacking interactions. There is one intramolecular O-H...O hydrogen bond in (II), and a combination of one three-centre N-H...(N,O) hydrogen bond [H...N = 2.46 A, H.O = 2.31 A, N...N = 3.190 (2) A, N...O = 3.146 (2) A, N-H...N = 138 degrees and N-H...O = 154 degrees ] and one two-centre C-H...O hydrogen bond [H.O = 2.46 A, C...O = 3.405 (2) A and C-H...O = 173 degrees ] links the molecules into sheets. In (III), an intramolecular O-H...N hydrogen bond and two N-H...O hydrogen bonds [H...O = 2.26 and 2.10 A, N...O = 2.975 (2) and 2.954 (2) A, and N-H...O = 138 and 163 degrees ] link the molecules into sheets.
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