The 1:1 co-crystal of 2-bromonaphthalene-1,4-dione and 1,8-dihydroxyanthracene-9,10-dione: crystal structure and Hirshfeld surface analysis

Abstract

The asymmetric unit of the title co-crystal, C10H5BrO2·C14H8O4 [systematic name: 2-bromo-1,4-dihydronaphthalene-1,4-dione–1,8-dihydroxy-9,10-dihydroanthracene-9,10-dione (1/1)], features one molecule of each coformer. The 2-bromonaphthoquinone molecule is almost planar [r.m.s deviation of the 13 non-H atoms = 0.060 Å, with the maximum deviations of 0.093 (1) and 0.099 (1) Å being for the Br atom and a carbonyl-O atom, respectively]. The 1,8-dihydroxyanthraquinone molecule is planar (r.m.s. deviation for the 18 non-H atoms is 0.022 Å) and features two intramolecular hydroxy-O—H...O(carbonyl) hydrogen bonds. Dimeric aggregates of 1,8-dihydroxyanthraquinone molecules assemble through weak intermolecular hydroxy-O—H...O(carbonyl) hydrogen bonds. The molecular packing comprises stacks of molecules of 2-bromonaphthoquinone and dimeric assembles of 1,8-dihydroxyanthraquinone with the shortest π–π contact within a stack of 3.5760 (9) Å occurring between the different rings of 2-bromonaphthoquinone molecules. The analysis of the Hirshfeld surface reveals the importance of the interactions just indicated but, also the contribution of additional C—H...O contacts as well as C=O...π interactions to the molecular packing.