5,5'-[9H-fluoren-9-ylidenebis(4,1-phenyleneoxy)]bis-1,3-Isobenzofurandione

Preparation

5,5'-[9H-fluoren-9-ylidenebis(4,1-phenyleneoxy)]bis-1,3-Isobenzofurandione was synthesized according to the literature using a threestepsynthetic procedure starting from the nitro-displacement reactionof 4-nitrophthalonitrile with 9,9-bis(4-hydroxyphenyl)fluorene, in dryN,N-dimethylformamide (DMF), in the presence of potassium carbonate,at room temperature, followed by alkaline hydrolysis of thetetranitrile intermediate and dehydration with acetic anhydride of theresulting tetracarboxylic acid.