Crystal structure of 1-(methylsulfonyl)- 2-(p-methoxyphenylthio)ethane at 87 K. A comparative study of two different crystals

Abstract

The structure of l-(methylsulfonyl)-2-(p-methoxyphenylthio)ethane, C10H14O3S2, was determined from an X-ray diffraction study of two different crystals, A and B, at 87 K. The space group is monoclinic, Pljc, a = 10.859(1), b = 5.310(1), c = 19.934 (3) 98.49(2)° and Z = 4 from high-order reflections for crystal B. Intensities were collected to (sin 0)ß = 0.650 for crystal A and to 0.904 Ä"' for B with MoÄa radiation. The structure was solved by direct methods. Parameters derived for crystal A (Ä = 0.029 for 2418 FJ and from the data with (sin0)/ X < 0.650 Ä"' for B (Ä = 0.032 for 2402 F,) were compared and analysed by half-normal probability plots and by x^ tests. The agreement is very good. The slopes in all plots are < 1.0 indicating a slight overestimation of the Standard deviates. A normal probability plot of the two sets of observed F^ [(sin 9)/X < 0.65 Ä~'] has a siope very dose to 1.0. Least-squares refmements have been carried out with various subsets of data for crystal B. The Parameters from the refmement with (sin 0)/A > 0.75 Ä"' were taken to give the best description of the structure (/? = 0.027, 1387 F"). The refined bond lengths in the fragment containing S and the phenyl ring were corrected for thermal motion. Before correction the ring C -C bonds are about 0.0034 Ä longer than the values from the refinement with all data. Bonding Parameters at the S atoms corroborate previous observations for some closely related sulfide and sulfone structures. The distortions from €2« symmetry in the para-substituted phenyl ring is largely effected by the OCH 3 group which is confirmed from a comparison of various parasubstituted anisoles. The observed reversible change in colour of the crystals, from colourless at room temperature to pale purple at 87 K seems to be related to a shortening of an intermolecular S • • • Ph contact.