Crystal structure and Hirshfeld surface analysis of dimethyl (1R∗,3aS∗,3a1R∗,6aS∗,9R∗,9aS∗)-3a1,5,6,9a-tetrahydro-1H,4H,9H-1,3a:6a,9-diepoxyphenalene-2,3-dicarboxylate

The title diepoxyphenalene derivative, C 17 H 18 O 6 , comprises a fused cyclic system containing four five-membered rings (two dihydrofuran and two tetrahydrofuran) and one six-membered ring (cyclohexane). The five-membered dihydrofuran and tetrahydrofuran rings adopt envelope conformations, and the six-membered cyclohexane ring adopts a distorted chair conformation. Two methyl carboxylate groups occupy adjacent positions (2- and 3-) on a tetrahydrofuran ring. In the crystal, two pairs of C-H O hydrogen bonds link the molecules to form inversion dimers, enclosing two R2 2(6) ring motifs, that stack along the α-axis direction and are arranged in layers parallel to the bc plane. © 2019 International Union of Crystallography. All rights reserved.