The competition between halogen bonds (Br⋯O) and C–H⋯O hydrogen bonds: the structure of the acetone–bromine complex revisited

Jones, R. H.; Knight, K. S.; Marshall, W. G.; Coles, S. J.; Horton, P. N.; Pitak, M. B.

Abstract

A combination of single-crystal X-ray (at 110 and 200 K) and high-resolution neutron powder diffraction (110 K only) using perdeuterated samples has been used to re-determine the crystal structure of the well-known acetone–Br2 complex. The results indicate a significant interaction between the carbonyl oxygen and the nearest Br atom leading to a marked elongation of the molecular Br–Br bond. In the earlier widely cited crystal structure, no such elongation was reported. Furthermore, the new structure indicates the presence of additional weaker C–H⋯O and C–H⋯Br interactions. In this simple complex, in which the halogen bonding is strong compared to the hydrogen bonding (C–H⋯O), the former interaction is found to occur close (~12°) to the plane of the carbonyl group, with the C–H⋯Br complementing the stronger halogen bond.

Citation

Jones, R. H., Knight, K. S., Marshall, W. G., Coles, S. J., Horton, P. N., & Pitak, M. B. (2013). The competition between halogen bonds (Br⋯O) and C–H⋯O hydrogen bonds: the structure of the acetone–bromine complex revisited. CrystEngComm, 15(42), 8572. https://doi.org/10.1039/c3ce41472h

• Journal Article Type: Article
• Acceptance Date: Sep 4, 2013
• Online Publication Date: Sep 6, 2013
• Publication Date: 2013
• Deposit Date: Jun 16, 2023
• Journal: CrystEngComm
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 15
• Issue: 42
• Pages: 8572
• DOI: https://doi.org/10.1039/c3ce41472h
• Keywords: Condensed Matter Physics; General Materials Science; General Chemistry