Noncovalent π-π interactions between chloroboron subphthalocyanine (1), 2,3-subnaphthalocyanine (3), 1,4,8,11,15,18-(hexathiophenyl)subphthalocyanine (4), or 4-tert-butylphenoxyboron subphthalocyanine (2) with C and C fullerenes were studied by UV-vis and steady-state fluorescence spectroscopy, as well as mass (APCI, ESI, and CSI) spectrometry. Mass spectrometry experiments were suggestive of relatively weak interaction energies between compounds 1-4 and fullerenes. The formation of a new weak charge-transfer band in the NIR region was observed in solution only for subphthalocyanine 4 when titrated with C and C fullerenes. Molecular structures of the subphthalocyanines 2 and 4 as well as cocrystallite of 4 with C fullerene (4···C) were studied using X-ray crystallography. One of the C fullerenes in the crystal structure of 4···C was found in the concave region between two subphthalocyanine cores, while the other three fullerenes are aligned above individual isoindole fragments of the aromatic subphthalocyanine. The excited-state dynamics in noncovalent assemblies were studied by transient absorption spectroscopy. The time-resolved photophysics data suggest that only electron-rich subphthalocyanine 4 can facilitate an electron-transfer to C or C fullerenes, while no electron-transfer from the photoexcited receptors 1-3 to fullerenes was observed in UV-vis and transient spectroscopy experiments. DFT calculations using the CAM-B3LYP exchange-correlation functional and the 6-31+G(d) basis set allowed an estimation of interaction energies for the noncovalent 1:1 and 1:2 (fullerene:subphthalocyanine) complexes. Theoretical data suggest that the weak (∼3.5-10.5 kcal/mol) van der Waals-type interaction energies tend to increase with an increase of the electron density at the subphthalocyanine core with compound 4 being the best platform for noncovalent interactions with fullerenes. DFT calculations also indicate that 1:2 (fullerene:subphthalocyanine) noncovalent complexes are more stable than the corresponding 1:1 assemblies.

Mono-and di-(N-ferrocenyl-2-pyridone)-containing BODIPYs were prepared using a set of ferrocene-enamine cyclization reactions. The target compounds were characterized by UV-Vis, NMR, and mass spectrometry, while their redox properties were probed by the electrochemical, spectroelectrochemical, and chemical oxidation methods. Redox properties of the di-(ferrocenyl)-containing BODIPY are suggestive of a lack of electronic coupling between the two ferrocene groups. Oxid-

As eries of covalent ferrocene-BODIPY-fullerene triads with the ferrocene groups conjugated to the BODIPY p-systema nd the fullerene acceptorl inked at the boron hub by ac ommon catecholpyrrolidine bridge were prepared and characterizedb y1 Da nd 2D NMR, UV/Vis, steady-state fluorescence spectroscopy, high-resolution mass spectrometry, and, for one of the derivatives, X-ray crystallography.R edox processes of the new compounds were investigated by electrochemical (CV and DPV) methods and spectroelectrochemistry.D FT calculations indicate that the HOMOin all triads was delocalized between ferrocene and BODIPY p-system, the LUMO was always fullerene-centered, and the catecholcentered occupied orbitalw as close in energy to the HOMO. TDDFT calculations were indicative of the low-energy,l ow-in-tensity charge-transfer bands originated from the ferrocene-BODIPY core to fullerene excitation, which explainedt he similarity of the UV/Vis spectra of the ferrocene-BODIPY dyadsa nd ferrocene-BODIPY-fullerene triads. Photophysical properties of the new triadsa sw ell as reference BODIPYfullerenea nd ferrocene-BODIPY dyads were investigated by pump-probe spectroscopy in the UV/Vis and NIR spectralr egions following selective excitation of the BODIPY-based antenna.I nitial charget ransfer from the ferrocenet ot he BODIPY core was shown to outcompetes ub-100 fs deactivation of the excited state mediated by the catecholb ridge. However, no subsequente lectron transfer to the fullerene acceptorw as observed. The initial charge separated state relaxes by recombination with at ime constanto f1 50-380 ps.[a] Dr.We attempted to obtain single crystals of triads 3a-d.I nt he majority of cases, crystals were too small for X-ray crystallographic measurements, with typical reflection datal imited to Scheme1.Synthetic pathway for preparation of the ferrocene-BODIPY-fullerene triads 3a-d.

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