The effect of introduction of perfluoro alkyl groups into phthalocyanines, as evidenced by the spectroscopic properties of 1,4,8,11,15,18,22,25-octa-fluoro-2,3,9,10,16,17,23,24-octa-perfluoro isopropyl zinc phthalocyanine, ZnF(64)Pc(-2) and its ring-reduced radical anion species, [ZnF(64)Pc(-3)](-), are reported. A combination of UV-visible absorption and magnetic circular dichroism (MCD) spectroscopy, ESI and MALDI-TOF mass spectrometry, cyclic and differential pulse voltammetry, and complete theoretical calculations using INDO/S and DFT techniques reveals that the substitution of all sixteen hydrogen atoms in protio ZnPc(-2) by eight F and eight i-C(3)F(7) groups red shifts the Q and pi --> pi transitions and narrows the HOMO-LUMO gap while simultaneously preventing ring photooxidation and stabilizing the radical anion. The [ZnF(64)Pc(-3)](-) species, which is in equilibrium in solution with the neutral complex when a reducing agent is present, is unusually stable. The above effects are attributed to the strong electron withdrawing properties of the peripheral substituents, which render ZnF(64)Pc extremely electron deficient.

Hohe Antitumor‐Aktivität zeigt das erste sterisch gehinderte (nichtplanare), perhalogenierte Zink‐Phthalocyanin (Pc), [F64PcZn(Aceton)2], im Vergleich zu planarem Zinkperfluorphthalocyanin (siehe Struktur: F grün, N blau, O rot, C grau). Die Perfluorisopropyl‐Substituenten erhöhen die Löslichkeit, stabilisieren die axialen Liganden (wie die koordinierten Acetonmoleküle in der abgebildeten Struktur), verkleinern die HOMO‐LUMO‐Lücke, verändern die Redoxpotentiale und verlängern die Lebenszeit des angeregten Triplettzustandes des neuen Komplexes.