Efficient green procedures for the preparation of novel tetraalkynyl-substituted phthalocyanines

This work provides a successful, easy and efficient process for the preparation of metal-free 2(3),9(10),16(17),23(24)-octamethoxyphthalocyanine, [(OMe)8PcH2] (2), and its metal complexes [(OMe)8PcM] (3–11) (M = Zn, Cu, Ni, Mg, Co, Fe, Ru, TiCl and RhCl) by using green energy techniques such as exposure to UV-irradiation as well as microwave irradiation. Two different routes have been used, which involve modifications to that reported in the literature. The results suggest that these techniques drastically reduce the reaction time of metallophthalocyanine [(OMe)8PcM] (3–11) formation from 5–96 h to 5–11 min. The prepared octamethoxyphthalocyanines [(OMe)8PcM] (2–4) (M = H2, Zn, Cu) are used as key materials to synthesize the corresponding novel tetraalkynyl-substituted phthalocyanines 15–17.