Characterization of a new asymmetrically substituted metal-free phthalocyanine

The present publication is devoted to the characterization of a new asymmetrically substituted metal-free phthalocyanine. After chemical modification by attaching donor-acceptor substituents to its peripheral ring, the phthalocyanine derivative becomes a polarized molecule, and shows dipole moment of 3.8 D in benzene. Comparision with symmetrical tetra-t-butylphthalocyanine (BuPc), the oxidation peak potential of nitro-tri-t-butylphthalocyanine (NtBuPc) is 0.08 volt higher than that of BuPc as a result of electron-withdrawing nitro group. Thermogravimetry analysis indicates that the initial decomposition temperature of NtBuPc is as high as 389 °C, exhibiting good thermal stability.