Publications [#233551] of Andrew T. McPhail
Journal Articles
- McPhail, AT; Onan, KD; Gross, PM, "X-ray determination of the structure and conformation of an oxide from helenalin", Journal of the Chemical Society Perkin Transactions 2January,, 1975(5), 496-500, Royal Society of Chemistry (RSC) [Gateway.cgi], [doi].
(last updated on 2026/01/21)Abstract:
The crystal and molecular structure of the oxide (II) produced by the reaction of helenalin (I) with hydrogen chloride-chloroform and deactivated neutral alumina has been established by X-ray analysis from photographic data. Crystals are orthorhombic, space group P21 21 21 , with a = 8.57(1), b = 15.79(2), c = 9.95(1) Å, Z = 4. The structure was solved by direct phase-determining methods and the molecular parameters refined by full-matrix least-squares calculations to R 0.117 over 1303 independent observed reflections. The cycloheptane ring adopts a conformation intermediate between the twist-chair and chair forms.