Weak inter-actions in the crystal structures of two indole derivatives
Jamie R Kerr1, Laurent Trembleau1, John M D Storey1
1Department of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, Scotland.
Abstract:
We describe the syntheses and crystal structures of two indole derivatives, namely a second monoclinic polymorph of ethyl 5-chloro-1H-indole-2-carboxyl-ate C11H10ClNO2, (I), and ethyl 5-chloro-3-iodo-1H-indole-2-carboxyl-ate, C11H9ClINO2, (II). In their crystal structures, both compounds form inversion dimers linked by pairs of N-H⋯O hydrogen bonds, which generate R 2 (2)(10) loops. The dimers are linked into double chains in (I) and sheets in (II) by a variety of weak inter-actions, including π-π stacking, C-I⋯π, C-Cl-π inter-actions and I⋯Cl halogen bonds.
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