Polyketone synthesis involving nucleophilic substitution via carbanions derived from bis(alpha-amino nitrile)s .2. Wholly aromatic polyketones without ether linkages

To address the insolubility problem of polyketones, we used a new approach to high molecular weight wholly aromatic polyketones without ether linkages via soluble precursors derived from isophthaldehyde-based amino nitriles.(1) High molecular weight, soluble poly(amino nitrile)s 2 were synthesized from the anions of these bis(amino nitrile)s 1 and 4,4'-difluorobenzophenone using sodium hydride as base under mild reaction conditions. Hydrolysis of the poly(amino nitrile)s under acidic conditions yielded the corresponding polyketone, poly(p-phenylenecarbonyl-p-phenylenecarbonyl-m-phenylenecarbonyl) (3). This all aromatic polyketone, with an absence of ether linkages in the polymer backbone, displays excellent thermal properties and solvent resistivity. It is infusible and insoluble in most common organic solvents.