A 3,5-dinitrobenzoyl derivative of a stereoisomer of glycerol menthonide

• Published in: Acta crystallographica. Section E, Structure reports online Vol. 65; no. 7; p. o1540
• Main Authors: Kiessling, Anthony, Campana, Charles, Kastner, Margaret E.
• Format: Journal Article
• Language: English
• Published: International Union of Crystallography 01.07.2009
• ISSN: 1600-5368; 1600-5368
• DOI: 10.1107/S1600536809020960

The title compound, [(2S,5R,6S,9R)-6-isopropyl-9-methyl-1,4-dioxaspiro[4.5]dec-2-yl]methyl 3,5-dinitrobenzoate, C20H26N2O8, was synthesized as part of a study of three-carbon stereochemical systems. The crystallographic assignment of the absolute stereochemistry is consistent with having started with (−)-menthone, the acetal carbon is R and the secondary alcohol is S. This brings the dinitrobenzoate into approximately the same plane as the menthyl ring and anti to the isopropyl group. Close intermolecular C=O...NO2 contacts between neighboring molecules [2.8341 (16) Å] contribute to the packing arrangement. The structure was refined as a pseudo-merohedral twin (monoclinic space group P21 emulating the orthorhombic space group C2221). Application of the twin law 100, 0overline{1}0, overline{1}0overline{1} gave a 2:1 ratio of twin moieties [refined BASF value = 0.3790 (7)].