Dioxo derivatives of benzenoid hydrocarbons: Part IV - Dioxo-bisanthrenes

Abstract

<span style="font-size:14.0pt;font-family:" times="" new="" roman";="" mso-fareast-font-family:"times="" roman";mso-ansi-language:en-us;mso-fareast-language:="" en-us;mso-bidi-language:ar-sa"="">Depending on the position of the two oxo groups, isomeric dioxo derivatives of benzenoid hydrocarbons drastically differ in the extent and mode of π-electron conjugation. We report here the results of AMI studies of the 14 Kekulean dioxo derivatives of bisanthrene (phenanthro-( 1,10<span style="mso-bidi-font-style:italic">,9,8<i>-o,p,q,r,a]perylene). </i>Our calculations indicate that in this case also the relative stabilities and the geometries of the dioxo derivatives are predominantly determined by π -electron conjugation and to a lesser extent by steric repulsion of the oxo groups in positions 3,4,10 and/or 11 , and by electrostatic repulsion of near-lying oxo groups.</span></span>