| abstract |
A process for the preparation of 4,4'-dinitro-2,2'-di(trifluoromethyl)diphenyl ether according to the equation ##STR1## where X is F, Cl, Br or I, where the inorganic base is selected from the group consisting of alkali metal hydroxides, alkali metal carbonates, and alkali metal bicarbonates, in the presence of a catalytic quantity of a benzoate catalyst. 2,8-Dinitro-6,6,12,12,-tetrafluoro-6H,12H-dibenzo[b,f][1,5]dioxocin, the corresponding diamine and polyimides formed from the diamine are also disclosed. |