Skip to Main Content
U.S. Forest Service
Caring for the land and serving people

United States Department of Agriculture

Home > Search > Publication Information

  1. Share via EmailShare on FacebookShare on LinkedInShare on Twitter
    Dislike this pubLike this pub
    Author(s): Frank R. Fronczek; Garret Gannuch; Wayne L. Mattice; Richard W. Hemingway; Giacomo Chiari; Fred L. Tobiason; Karl Houglum; Armen Shanafelt
    Date: 1985
    Source: Journal of the Chemical Society Perkin Trans II:1383-1386
    Publication Series: Miscellaneous Publication
    PDF: Download Publication  (1.1 MB)


    The structure of penta-O-acetyl-(+)-catechin has been determined in the crystalline state. Crystals are monoclinic, space group C2, a=2320.0(7), b=980.1 (2), c=1108.0(3) pm, β=100.64(2)., Z=4, Dc=1.342 g cm-3, R=0.058 for 1121 observations. One of the acetyl groups is disordered. Axial positions are occupied by the substituents bonded to heterocyclic ring atoms C(2) and C(3). The substituent bonded to C(2) occupies an equatorial position in previously reported crystal structures for related compounds. The root-mean-square dipole moment is 3.67 ± 0.26 D in dioxane at 25°C. Conformational analysis demonstrates that the measured dipole moment in dioxane can be expected if either the same ring geometry or a diequatorial form occurs in solution. 1H N.m.r. coupling constants J2-3 6.5, J3-4 5.0, and J3-4 7.0 Hz suggest a heterocyclic ring conformation between these two extremes or a rapid flexing of the heterocyclic ring in solution at ambient temperature. Spectra recorded at -90°C do not show a preferred conformation. Instead they show a slow exchange between different conformations of the heterocyclic ring.

    Publication Notes

    • You may send email to to request a hard copy of this publication.
    • (Please specify exactly which publication you are requesting and your mailing address.)
    • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.


    Fronczek, Frank R.; Gannuch, Garret; Mattice, Wayne L.; Hemingway, Richard W.; Chiari, Giacomo; Tobiason, Fred L.; Houglum, Karl ; Shanafelt, Armen. 1985. Preference for occupany of axial positions by substituents bonded to the heterocyclic ring in penta-O-acetyl-(+)-catechin in the crystalline state. Journal of the Chemical Society Perkin Trans II:1383-1386

    Related Search

    XML: View XML
Show More
Show Fewer
Jump to Top of Page