The functionalized, asymmetric fluoro-fluoroalkyl scaffold FHCOOHPcZn (3) was used to prepare FHCOOPcZn-6-amino-hexanoate-CTVALPGGYVRVC (5), a Pep42 peptide bioconjugate envisioned for photodynamic therapy, which can specifically target the GRP78 chaperone protein overexpressed and exclusively localized on some cancer cell surfaces. The analogous FHCOOHPcCu (4) has also been prepared, and its single-crystal X-ray structure was elucidated. Despite reduced steric hindrance relative to the nonfunctionalized, single-site complexes of the FPc scaffold, no aggregation was detected in solution via UV-vis spectroscopy, for either 3, 4, or 5, consistent with the lack of π stacking observed for the crystalline 4. The 6-aminohexanoic acid-Pep42 moiety diminishes the fluorescence efficiency of 5, relative to 3, but for singlet oxygen (O) generation, photochemical hydroperoxidation of β-(-)-citronellol using 5 and 3 occurs with comparable substrate turnover efficiency, albeit at a slower initial triplet oxygen uptake for 5. The bioconjugate 5 is durable; it does not decompose under O photoreaction conditions. These results suggest a synthetic coupling pathway for obtaining diverse biotargeting polypeptide-fluorinated phthalocyanine bioconjugates of potential utility as both fluorescence reporters and photocatalysts and highlight the importance of fluorinated scaffolds for generating chemically resilient, catalytic, theranostic materials.

We report the synthesis, redox and photo-physical properties, as well as singlet oxygen reactivity of the first representatives of Group III perfluoroalkyl perfluoro metal phthalocyanines, gallium and indium complexes. Microwave-assisted synthesis was used to produce F[Formula: see text]PcM, M [Formula: see text] Ga, In in reasonable yields. Both Ga and In complexes exhibit high thermal and chemical stability properties, attributed to the perfluoroalkyl perfluoro phthalocyanine ligand. Electrochemical and spectroelectrochemical measurements show reversible redox processes for both compounds, including spontaneous re-oxidations following electrochemical or photochemical reductions. No electrochemical or chemical oxidations of the neutral complexes are observed. Photo-hydroperoxidation of ([Formula: see text]-(-)-citronellol occurs with rates of 13.5 and 1.7 [Formula: see text]mol O2 min[Formula: see text] mol[Formula: see text] Pc and substrate turnovers of 225 and 28.2 mmol ([Formula: see text]-Cit s[Formula: see text] mol[Formula: see text] Pc for the In and Ga complexes, respectively. The solid state materials are stable and can be sublimed at temperatures higher than 380°C. Related complexes are candidates for similar chemistry and photophysics based on the observation that the fluorinated ligand determines most of the favorable properties.