Kumar Biradha, Ashwini Nangia, Gautam R. Desiraju, C. J. Carrell and H. L. Carrell
Dibenzylideneacetone1a, 2,5-dibenzylidenecyclopentanone 1b, 2,6-dibenzylidenecyclohexanone 1c and 2,5-dibenzylidenecyclopent-3-enone 1d form crystalline stoichiometric complexes with 1,3,5-trinitrobenzene 2a, picryl chloride 2b and picric acid 2c. The structures of these complexes are mediated by multi-point C–HO hydrogen bonds. Some of these patterns of molecular recognition also contain stronger O–HO hydrogen bonds. The C–HO hydrogen bonds within these multi-point supramolecular synthons are generally shorter and more linear than the other C–HO hydrogen bonds found in these complexes.