CRYSTAL-STRUCTURE OF IMETHYL-5-OXA-3-THIATRICYCLO[9.2.1.0(1,6)]UNDECANE

Crystals of the optically active C18H22O3S, [alpha]D20= +101-degrees, have been studied by X-ray diffraction methods. The crystals arc monoc linic, P2(1), a = 7.493(1), b = 10.778(3), c = 9.919(4)angstrom, beta = 94.11(2)-degrees, Z = 2. The structure was solved by direct methods and refined to R = 0.036 for 2742 observed reflections. The methylened ioxyphenyl fragment of the molecule shows some deformations from plana rity, the 1,3-oxathiane ring adopts a chair conformation and the subst ituent at position 2 is situated equatorially. The new asymmetry cente r at C2 shows R absolute configuration.