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chromatography (SiO2, CH2Cl2) gave A (102 mg, 83%). dH
(CDCl3) 0.88 (t, J 7, 6H), 1.20–1.50 (m, 36H), 1.80 (m, 4H), 3.97
(t, J 7, 4H), 5.58 (s, 2H), 6.39 (t, J 2, 1H), 6.66 (d, J 2, 2H), 7.06
(AB, J 16, 2H), 7.30–7.45 (m, 5H), 7.54 (d, J 8, 2H), 7.67 (s, 1H),
7.79 (d, J 8, 2H). dC (CDCl3) 14.1, 22.7, 26.1, 29.3, 29.35, 29.4,
29.55, 29.6, 29.65, 29.7, 31.9, 54.3, 68.1, 101.1, 105.1, 119.4,
125.9, 127.0, 128.1, 128.4, 128.8, 129.1, 129.2, 129.7, 134.6,
137.1, 139.1, 160.5. m/z 706.5 ([M þ H]þ, 100%), 679 ([M þ H ꢁ
N2]þ, 10), 586 ([M þ H ꢁ PhCH2N2]þ, 2), 572 ([M þ H ꢁ
PhCH2N3]þ, 2). Anal. Calc. for C47H67N3O2: C 79.95, H 9.56,
N 5.95. Found: C 79.57, H 9.52, N 5.89%.
Steady-state photoluminescence spectra were recorded in
right angle mode with an Edinburgh FLS920 spectrometer
(continuous 450 W Xe lamp), equipped with a Peltier-cooled
Hamamatsu R928 photomultiplier tube (185–850 nm). The
concentration of air-equilibrated sample solutions was adjusted
to obtain absorption values A o0.15 at the excitation wave-
length. Emission quantum yields were determined according to
the approach described by Demas and Crosby,[20] using Quinine
sulfate (Fem ¼ 0.546 in air-equilibrated acid water solution, 1 N
H2SO4) and [Ru(bpy)3Cl2] (Fem ¼ 0.028 in air-equilibrated
water solution)[21] as standards. One cm path length square
optical Suprasil Quartz (QS) cuvettes were used for measure-
ments at RT of dilute solutions, while capillary tubes immersed
in liquid nitrogen in a coldfinger quartz Dewar were used for
measurements of solvent frozen glasses at 77 K.
Compound C60(A)12
CuSO4ꢀ5H2O (2 mg, 0.011 mmol) was added to a mixture of 6
(831 mg, 1.451 mmol), 7 (260 mg, 0.111 mmol), and sodium
ascorbate (7 mg, 0.033 mmol) in CH2Cl2/H2O (1:1, 6 mL) at
room temperature. The reaction mixture was stirred for 48 h.
The organic layer was diluted with CH2Cl2, washed with water,
dried (Na2SO4), filtered, and concentrated. Column chromato-
graphy (SiO2, CH2Cl2/MeOH 99:1) followed by GPC gave
C60(A)12 (640 mg, 62%). dH (CDCl3) 0.89 (t, J 7, 72H), 1.20–
1.50 (m, 432H), 1.66–1.85 (m, 48H), 2.37 (m, 24H), 3.93 (t,
J 7, 48H), 4.40 (m, 48H), 6.38 (broad t, J 2, 12H), 6.62 (broad d,
J 2, 24H), 7.00 (broad s, 24H), 7.45 (broad d, J 7, 24H), 7.75 (m,
36H). dC (CDCl3) 14.0, 22.6, 26.0, 27.3, 28.9, 29.3, 29.4, 29.6,
29.65, 31.9, 45.4, 47.8, 63.7, 68.0, 69.1, 101.0, 105.0, 120.0,
125.9, 127.0, 128.2, 129.1, 129.4, 137.1, 138.9, 141.2, 145.8,
147.5, 160.4, 163.4. nmax/cmꢁ1 1744 (C¼O). m/z 9206
([M þ H]þ, 27%), 8633 ([M þ H ꢁ (C40H60O2)1]þ, 52), 8060
([M þ H ꢁ (C40H60O2)2]þ, 83), 7488 ([M þ H ꢁ (C40H60O2)3]þ,
100), 6915 ([M þ H ꢁ (C40H60O2)4]þ, 90), 6342 ([M þ H ꢁ
(C40H60O2)5]þ, 75), and 5769 ([M þ H ꢁ (C40H60O2)6]þ, 60).
Anal. Calc for C594H792N36O48: C 77.51, H 8.67, N 5.48. Found:
C 77.82, H 8.59, N 5.40%.
Fluorescence lifetimes were measured with an IBH 5000F
time-correlated single-photon counting device, by using pulsed
NanoLED excitation source at 331 nm. Analysis of the lumines-
cence decay profiles against time was accomplished with the
Decay Analysis Software DAS6 provided by the manufacturer.
Acknowledgements
This research was supported by the EC (contract PITN-GA-2008–215399 –
FINELUMEN), the CNRS, the University of Strasbourg and the CNR
(commessa PM.P04.010, MACOL). J.I. thanks the French Ministry of
Research and the University of Strasbourg for his fellowship. J.M.M. thanks
the Institute of Advanced Studies of the University of Bologna for her fel-
lowship. We further thank A. Saquet for her help with the electrochemical
measurements and M. Schmitt for the NMR spectra.
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Electrochemistry
The CV measurements were carried out with a potentiostat
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compound and 0.1 M for the supporting electrolyte. Before each
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Photophysics
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The photophysical studies were carried out in dichloromethane
(Carlo Erba, spectrofluorimetric grade). Absorption spectra
were recorded with a Perkin–Elmer Lambda 950 UV/vis/NIR
spectrophotometer. Molar absorption values (e) were calculated
by applying the Lambert–Beer law to the absorbance spectra
(Amax o0.7) of the compounds.