(1R*,2R*,3S*,4R*)-Diethyl 4-hydroxy-4-methyl-2-(4-methylphenyl)-6-oxocyclohexane-1,3-dicarboxylate

Abstract

Key indicators: single-crystal X-ray study; T = 296 K; mean (C-C) = 0.003 Å; disorder in main residue; R factor = 0.053; wR factor = 0.141; data-to-parameter ratio = 17.7.The title compound, C 20 H 26 O 6 , is chiral and crystallizes as a racemate: the relative configuration of the stereogenic centres is 1R*,2R*,3S*,4R*. The cyclohexane ring has a chair conformation. The ethyl fragment of the ethoxycarbonyl group in the 3-position is disordered over two sets of sites in a 0.650 (6):0.350 (6) ratio. The hydroxy group acts as a bifurcated hydrogen-bond donor, forming both intra-and intermolecular hydrogen bonds with ester carbonyl O atoms. The intermolecular hydrogen bonds form inversion dimers in the crystal. Related literatureFor applications of related compounds as synthetic intermediates, see: Gein et al. (2003Gein et al. ( , 2004 Sorokin et al. (2000). ExperimentalCrystal data