One-Step Thermo-Mechanochemical Syntheses of Metal Phthalocyanines and Polyphthalocyanines

We present a thermo-mechanochemical synthesis of metal phthalocyanines with varying metal centers and building blocks. The reactions were performed using a Retsch Mixer Mill 400 equipped with heating jackets, achieving quantitative yields at 120 °C within 2 h. A systematic screening of reaction parameters, including temperature, reaction time, frequency, and liquid-assisted grinding (LAG), revealed that temperature and time significantly influence the reaction outcome, as well as the use of LAG compared to neat grinding, which further enhances the yield. Powder X-ray diffraction analysis of the obtained metal phthalocyanines confirmed the presence of different polymorphs, suggesting a correlation between reaction conditions and crystallinity. Furthermore, the crystalline cobalt polyphthalocyanine (CoPPc) was successfully synthesized with a yield of >99%.