Received 28 September 2012
The title compound, C15H22N2O3, was obtained as a by-product of oxidative cleavage of 1,3-dicyclohexyl-(3-oxo-2,3-dihydrobenzofuran-2-yl)imidazolidine-2,4-dione. Herein, we report the crystal structure of a second polymorph, which was obtained by crystallization from an ethanol solution at 253 K, instead of slow evaporation of the same solvent at room temperature. While the first polymorph [Talhi et al. (2011). Acta Cryst. E67, o3243] crystallized in the non-centrosymmetric space group P212121, this second polymorph crystallizes in the centrosymmetric space group P21/n. Compared to the first polymorph, in the crystal no C=OC=O interactions were found (CO intermolecular distance longer than 3.15 Å) and instead, close packing of individual molecular units is mediated by C-H and weak C-HO interactions.
For the structure of the orthorhombic polymorph and further background information to the study, see: Talhi et al. (2011). For general background on crystallographic studies by our research group of related compounds having biological activity, see: Fernandes et al. (2011); Loughzail et al. (2011). For determination of the melting point, see: Ulrichan & Sayigh (1965).
Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT-Plus (Bruker, 2005); data reduction: SAINT-Plus (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: NK2188 ).
The authors gratefully acknowledge the Fundação para a Ciência e a Tecnologia (FCT, MEC, Portugal), the European Union, QREN, FEDER, COMPETE for financial support by the strategic projects PEst-C/CTM/LA0011/2011 (to CICECO) and PEst-C/QUI/UI0062/2011 (to QOPNA), the R&D project PTDC/QUI-QUI/098098/2008 (FCOMP-01-0124-FEDER-010785), as well as the post-doctoral research grant SFRH/BPD/63736/2009 (to JAF). We further wish to thank the FCT for specific funding towards the purchase of the single-crystal X-ray diffractometer. We also thank the European Community's Seventh Framework Programme (FP7/2007-20139 under grant agreement No. 215009).
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