Synthesis of tetraalkyl naphthalene bisanhydride and its model condensations with amines

To improve the solubility of naphthalene bisanhydride (NTCA), four alkyl groups are incorporated to the naphthalene core via a five-step procedure. The new naphthalene bisanhydride derivative (TO-NTCA) shows much higher reactivity than the parent NTCA in the model condensations with ortho-diaminobenzene and 2-ethylhexylamine and gives corresponding soluble molecules with excellent yields. Hence, TO-NTCA is a potential monomer for condensations.