Synthesis and X-Ray Crystal Structure of 1,2,4,6,7,9-Hexafluorodibenzo- p-dioxin.

Abstract 1,2,4,6,7,9-Hexafluorodibenzo- p -dioxin was synthesized from 2,3,4,6-tetrafluorophenol in the presence of sodium-t-butylate. An X-ray structure analysis has been performed. The molecule is essentially planar and possesses a centre of inversion. The C-C bond distances range from 136.3(7) to 138.3(6) pm and the C-F distances from 133.8(5) to 134.5(6) pm. The C-O distances are 137.8(5) and 139.1(6) pm, respectively.