Synthesis of Perfluoroanthraquinone and Aminoperfluoroanthraquinones

Abstract

Syntheses of perfluoroanthraquinone and novel aminoperfluoroantraquinones were investigated. One-step reaction between tetrachlorophthalic anhydride and potassium fluoride in an autoclave at 300°C afforded a mixture of perfluoroanthraquinone (F₈AQ), chloroheptafluoroanthraquinone (F₇ClAQ), and dichlorohexafluoroanthraquinone (F₆ClAQ). It was more conveniently prepared from the reaction in a Pyrex glass ware at 370°C under atmospheric nitrogen followed by subsequent sublimation. Pure F₈AQ was revealed to be obtained by thorough fluorination of the above mixture of F, AQ, F₇AQCl, and F₆Cl₂AQ with spray-dried potassium fluoride at 150°C in sulfolane.
Amination of F₈AQ by ammonia in tol uene afforded 1-aminoperfluoroanthraquinone and 2-aminoperfluoroanthraquinone (product ratio; 92: 8 at 110°C and 29: 71 at -35°C). Reaction of F₈AQ in liquid ammonia at -50°C led to a formation of 2, 6-diaminoperfluoroanthraquinone as a sole product.