Publications [#233531] of Andrew T. McPhail

Journal Articles

  1. McPhail, AT; Onan, KD; Koskimies, J, "X-ray crystal structure conformational studies on r-4,c-6-dimethyl-1,3- dithian and its oxides, r-4,c-6-dimethyl-1,3-dithian t-1-oxide, and r-4,c-6-dimethyl-1,3-dithian t-1,t-3-dioxide", Journal of the Chemical Society Perkin Transactions 2January,, 1976(9), 1004-1008, Royal Society of Chemistry (RSC) [Gateway.cgi], [doi].
    (last updated on 2026/01/21)

    Abstract:
    The crystal structures of the title compounds [the 1,3-dithian (I), and its oxides (II) and (III)] have been determined from X-ray diffractometer data. Monoclinic crystals of (I) and (II) are isomorphous, space group C2/c. with for (I) : a = 20.08(1), b = 5.71(1), c = 15.69(1) Å, β = 118.4(1)°: and for (II) : a = 20.33(1), b = 5.68(1), c = 16.11(1) Å, β = 119.0(1)°. Crystals of (III) are also monoclinic, space group P2 1/c, with a = 5.49(1), b = 15.52(1), c = 10.81(1) Å, β = 105.9(1)°. The structures were solved by the heavy-atom method and atomic parameters were refined by full-matrix least-squares calculations to R 0.047 (I), 0.044 (II), and 0.072 (III) over 1 129, 1 594, and 1 241 statistically significant reflections. In all three molecules the dithian rings adopt chair conformations which are increasingly more puckered as the number of substituents increases. The C-S distances in (I) and (II) reveal interesting differences which depend upon the degree of substitution at the carbon atoms.