Electrophilic aromatic aroylation polycondensation synthesis of wholly aromatic polyketone composed of 2,2′-dimethoxy-1,1′-binaphthylylene moiety

A wholly aromatic polyketone containing 2,2′-dimethoxy-1,1′-binaphthylylene moiety was successfully synthesized via electrophilic aromatic aroylation polycondensation with the aid of trifluoromethanesulfonic acid (TfOH) or phosphorus(V) oxide-methanesulfonic acid mixture (P2O5-MsOH). The polycondensation reactions employing two sets of monomers of opposite combination that should afford the same structure of repeating unit showed distinct results. The polycondensation employing 2,2′-dimethoxy-1,1′-binaphthyl (4) as the acyl-acceptant monomer proceeded to give medium-molecular-weight polymer. The polymer synthesis via transformation of biaryl 4 into the corresponding acyl-donor monomer 12 followed by polycondensation with 2,2′-dimethoxybiphenyl (1) predominated the procedure of direct usage of biaryl 4 as the acyl-acceptant monomer. Acyl-acceptant monomer has been demonstrated to play a more crucial role in determination of polymerizability than acyl-donor one.