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Photoinduced electron transfer in a clicked fullerene–porphyrin conjugate

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Julien Iehl at TEOXANE SA
Julien Iehl
  • TEOXANE SA
Maida Vartanian
Maida Vartanian
Maida Vartanian
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Michel Holler
Michel Holler
Michel Holler
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Jean-François Nierengarten at University of Strasbourg
Jean-François Nierengarten
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Abstract

A stable C60 derivative bearing an azide functional group has been prepared and used as a building block for the preparation of a fullerene–porphyrin conjugate (F–P–F) by reaction with a Zn(II)–porphyrin bearing two terminal alkynegroups under the copper mediated Huisgen 1,3-dipolar cycloaddition conditions. The electrochemical and photophysical properties of the resulting multicomponent system have been investigated in detail. In benzonitrile, F–P–F undergoes photoinduced electron transfer and the resulting charge separated state is relatively long lived (τ = 0.48 µs). In contrast, intramolecular energy transfer has been evidenced in toluene, with the generation of the fullerene triplet level upon selective excitation of the porphyrin moiety. In this solvent, a CT emission band is observed in the near-infrared region (λmax = 940 nm) as a consequence of a conformational equilibrium causing, to a minor extent, the formation of intramolecular porphyrin–fullerene tight pairs. This finding is supported by measurements of singlet oxygensensitization and quenching of the long-lived fullerene centered triplet state in the oxygen free solution.
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Supplementary Information
Photoinduced electron transfer in a clicked fullerene-porphyrin conjugate
Julien Iehl,a Maida Vartanian,a Michel Holler,a Jean-François Nierengarten,a* Béatrice Delavaux-
Nicot,b* Jean-Marc Strub,c Alain Van Dorsselaer,c* Yilei Wu,d John Mohanraj,d K. Yoosaf,d and
Nicola Armarolid*
a Laboratoire de Chimie des Matériaux Moléculaires, Ecole Européenne de Chimie, Polymères et
Matériaux, Université de Strasbourg et CNRS (UMR 7509), 25 rue Becquerel, 67087 Strasbourg
Cedex 2, France. E-mail: nierengarten@chimie.u-strasbg.fr
b Laboratoire de Chimie de Coordination du CNRS, 205 route de Narbonne, 31077 Toulouse Cedex 4,
France. E-mail: Beatrice.Delavaux-Nicot@lcc-toulouse.fr
c Laboratoire de Spectrométrie de Masse Bio-organique, Institut Pluridisciplinaire Hubert Curien
(IPHC), Ecole Européenne de Chimie, Polymères et Matériaux (ECPM), Université de Strasbourg et
CNRS (UMR 7178), 25 rue Becquerel, 67087 Strasbourg Cedex 2, France. E-mail:
vandors@chimie.u-strasbg.fr
d Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, via Gobetti
101, 40129 Bologna, Italy. E-mail: armaroli@isof.cnr.it
Supplementary Material (ESI) for Journal of Materials Chemistry
This journal is (c) The Royal Society of Chemistry 2010
Fig. S1. 2D NOESY spectrum of F-P-F recorded in CDCl3 at room temperature.
Fig. S2. OSWVs (cathodic and anodic scans) of compound F on a Pt electrode in CH2Cl2 + 0.1 M
nBu4NBF4 at room temperature.
Fig. S3. OSWVs (cathodic and anodic scans) of compound 12 on a Pt electrode in CH2Cl2 + 0.1 M
nBu4NBF4 at room temperature.
Fig. S4. Corrected singlet oxygen luminescence spectra of air-equilibrated solution containing P
(black), F (gray) and F-P-F (light gray). a) toluene: λexc = 550 nm, A = 0.300. b) benzonitrile: λexc =
560 nm, A = 0.300.
Fig. S5. Top: differential transient absorption spectra of P (grey dots), F (grey triangles, 0.7 x 10-4 M)
and F-P-F (black) obtained at 100 ns after nanosecond laser pulse per pulse irradiation at 560 nm in
deaerated benzonitrile at 298 K; inset: time profile of differential transient absorption spectra for F-P-
F obtained at 0-3.5 μs time intervals monitoring at 650 nm (λexc = 560 nm). Bottom: differential
transient absorption spectra of P (grey dots), F (grey triangles) and F-P-F (black) obtained at 100 ns
after nanosecond laser pulse irradiation at 560 nm in deaerated toluene at 298 K; the energy of the
laser used was 0.25, 1 and 2 mJ per pulse for P, F and F-P-F respectively. The intensity of the signals
is not directly comparable because the intensity of the laser and/or the concentration of the solution
were adjusted to observe the features of charge separation in F-P-F which are intrinsically weaker than
the triplet features of F and P, which also may undergo triplet –triplet annihilation phenomena at high
concentration or under high excitation power.
Supplementary Material (ESI) for Journal of Materials Chemistry
This journal is (c) The Royal Society of Chemistry 2010
Fig. S1 (A)
Supplementary Material (ESI) for Journal of Materials Chemistry
This journal is (c) The Royal Society of Chemistry 2010
Fig. S1 (B)
Supplementary Material (ESI) for Journal of Materials Chemistry
This journal is (c) The Royal Society of Chemistry 2010
Fig. S1 (C)
Supplementary Material (ESI) for Journal of Materials Chemistry
This journal is (c) The Royal Society of Chemistry 2010
Fig. S2
-0.5
-0.3
-0.1
-1.7-1.2-0.7-0.2
I / μA
E/ V versus SCE
0
0.2
0.4
0.6
0.8
00.511.522.5
I / μA
E / V versus SCE
Supplementary Material (ESI) for Journal of Materials Chemistry
This journal is (c) The Royal Society of Chemistry 2010
Fig. S3
-0.5
-0.3
-0.1
-1.8-1.3-0.8-0.3
I / μA
E / V versus SCE
0
0.1
0.2
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0.2 0.6 1 1.4
I / μA
E/ V versus SCE
Supplementary Material (ESI) for Journal of Materials Chemistry
This journal is (c) The Royal Society of Chemistry 2010
Fig. S4
1250 1300 13501250 1300 1350
λ / nm
b)
I / a.u.
λ / nm
a)
Supplementary Material (ESI) for Journal of Materials Chemistry
This journal is (c) The Royal Society of Chemistry 2010
Fig. S5
500 600 700 800 900 1000 1100 1200 1300
0.00
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0 2 4 6 8 10 12 14 16
0.00
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0.0 0.5 1.0 1.5 2. 0 2.5 3.0 3.5
0.00
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Δ A
λ / nm
Δ A
time / μs
Δ A
Δ A
time / μs
Supplementary Material (ESI) for Journal of Materials Chemistry
This journal is (c) The Royal Society of Chemistry 2010
... The conjugated nature of the linker might seem promising to drive eT across that bridge. However, its suitability as a linker in D-A dyads is disputed in literature; literature examples report on systems in which intramolecular eT across the triazole-bridge efficiently takes place within picoseconds [36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55] or nanoseconds [46,49,[71][72][73][74][75][76]. However, also systems are reported in which eT could not be observed at all, despite favorable thermodynamics [18,45,[56][57][58][59][60][61][62][63][64][65][66][67][68][69][70]77]. ...
... D1a and D1b, cf. Fig. 2a) [38,41,46,[48][49][50][51]57,[59][60][61][62][63]65,66,70,73,75,[78][79][80][81], followed by poly(fluorene) [40,44,45,52] and poly(thiophene) polymers [42][43][44], BODIPY (see D4a and D4b in Fig. 2a) [58,67,69,74,77,82] and organic push-pull dyes [36,37,54,83,84], as well as Ru II polypyridyl-type complexes (see D2a-c in Fig. 2a) [18,67,71,72,76,[85][86][87][88][89]. The most common acceptor units in D-A dyads are fullerenes [38,[48][49][50][51]53,54,59,60,70,73] (see A1 in Fig. 2b), diimide chromophores (see A3a and A3b in Fig. 2b) [46,55,72,[90][91][92], Dawson-type (a 2 -P 2 W 17 O 61 ) polyoxometalates (POMs, see A2 in Fig. 2b) [75,77,78,93], and metal complexes (e.g., with central Ru II [42][43][44][45]52,67,88,94], Fe IV [88], Ni II [87], Cu II [41,68,86], Co III [36,37,64,84,85], Re I - [76], or Rh III -ions [18], cf. ...
... Fig. 2a) [38,41,46,[48][49][50][51]57,[59][60][61][62][63]65,66,70,73,75,[78][79][80][81], followed by poly(fluorene) [40,44,45,52] and poly(thiophene) polymers [42][43][44], BODIPY (see D4a and D4b in Fig. 2a) [58,67,69,74,77,82] and organic push-pull dyes [36,37,54,83,84], as well as Ru II polypyridyl-type complexes (see D2a-c in Fig. 2a) [18,67,71,72,76,[85][86][87][88][89]. The most common acceptor units in D-A dyads are fullerenes [38,[48][49][50][51]53,54,59,60,70,73] (see A1 in Fig. 2b), diimide chromophores (see A3a and A3b in Fig. 2b) [46,55,72,[90][91][92], Dawson-type (a 2 -P 2 W 17 O 61 ) polyoxometalates (POMs, see A2 in Fig. 2b) [75,77,78,93], and metal complexes (e.g., with central Ru II [42][43][44][45]52,67,88,94], Fe IV [88], Ni II [87], Cu II [41,68,86], Co III [36,37,64,84,85], Re I - [76], or Rh III -ions [18], cf. A4 and A5 in Fig. 2b). ...
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  • COORDIN CHEM REV
In recent years, dyads in which molecular donor and acceptor moieties are chemically linked by a bridging ligand have emerged as attractive systems for light-driven catalysis. Their modular structure, controllable donor-acceptor distance, and their ability to undergo light-driven charge transfer, which is not limited by diffusion, render such systems promising in light-driven charge-transfer reactions and light-driven redox catalysis. Copper-catalyzed alkyne azide cycloaddition (CuAAC) is a particularly popular synthetic strategy for coupling donor and acceptor moieties. This CLICK chemistry approach yields dyads with a 1,2,3-triazole bridging motif. In this review, we discuss the complex role played by this triazole linker to drive electron transfer (eT) in a respective triazole-bridged donor-acceptor dyad upon photoexcitation. We review how structural and electronic properties of the bridge influence charge separation and recombination rates. Furthermore, the role of the triazole bridge energetics in thermal as well as oxidative and reductive photoinduced eT will be discussed. Finally, criteria for the design of dyads with different eT properties are derived.
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... With these crystals grown from toluene solution, they determined a distance from the centre of the porphyrazine to the centroid of the fullerene of 6.3 Å and they established the existence of van der Waals contact between them. As such there are numerous examples of combinations of porphyrins and fullerenes in the literature, both covalently (D'Souza et al., 2001;Imahori and Fukuzumi, 2004;Cho et al., 2005;Lehtivuori et al., 2006;Schuster et al., 2006;Umeyama and Imahori, 2006;Mathew et al., 2008;Iehl et al., 2011;Charvet et al., 2012;Tolkki et al., 2012) and noncovalently bound Konarev et al., 2002;Hasobe et al., 2005;D'Souza and Ito, 2009;Fathalla et al., 2009;Konarev et al., 2009;Nobukuni et al., 2009;Bhyrappa and Karunanithi, 2010;Hasobe, 2010;Oku et al., 2010;Wessendorf et al., 2010;Iehl et al., 2011;Kahnt et al., 2011;Sprafke et al., 2011;Wang et al., 2011;Konarev et al., 2012). ...
... With these crystals grown from toluene solution, they determined a distance from the centre of the porphyrazine to the centroid of the fullerene of 6.3 Å and they established the existence of van der Waals contact between them. As such there are numerous examples of combinations of porphyrins and fullerenes in the literature, both covalently (D'Souza et al., 2001;Imahori and Fukuzumi, 2004;Cho et al., 2005;Lehtivuori et al., 2006;Schuster et al., 2006;Umeyama and Imahori, 2006;Mathew et al., 2008;Iehl et al., 2011;Charvet et al., 2012;Tolkki et al., 2012) and noncovalently bound Konarev et al., 2002;Hasobe et al., 2005;D'Souza and Ito, 2009;Fathalla et al., 2009;Konarev et al., 2009;Nobukuni et al., 2009;Bhyrappa and Karunanithi, 2010;Hasobe, 2010;Oku et al., 2010;Wessendorf et al., 2010;Iehl et al., 2011;Kahnt et al., 2011;Sprafke et al., 2011;Wang et al., 2011;Konarev et al., 2012). ...
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ChemInform Abstract: Macrocyclization on the Fullerene Core: Direct Regio- and Diastereoselective Multi-Functionalization of [60]Fullerene, and Synthesis of Fullerene-Dendrimer Derivatives
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  • Jan 2010
  • ChemInform
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
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ChemInform Abstract: Synthesis, and Optical and Electrochemical Properties of Cyclophane-Type Molecular Dyads Containing a Porphyrin in Close, Tangential Orientation Relative to the Surface of trans-1 Functionalized C60
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The synthesis of the cyclophane-type molecular dyads 1 and 1·Zn was accomplished by Bingel macrocyclization of porphyrin-tethered bis-malonates 5 or 5·Zn, respectively, with C60 (Scheme). In these macrocycles, the doubly bridged porphyrin adopts a close, tangential orientation relative to the surface of the C-sphere. The porphyrin derivatives 6 and 6·Zn with two appended, singly-linked C60 moieties were also formed as side products in the Bingel macrocyclizations. The trans-1 addition pattern of the fullerene moiety in 1 and 1·Zn was unambiguously established by 1H- and 13C-NMR spectroscopy. Due to the close spatial relationship between the fullerene and porphyrin components in 1 and 6 and the corresponding ZnII complexes, the porphyrin fluorescence is efficiently quenched as compared to the luminescence emitted by 5 and 5·Zn, respectively (Fig. 2). Cyclic-voltammetry studies show that the mutual electronic effects exerted by the fullerene on the porphyrin and vice versa in 1 and 1·Zn are relatively small despite the close proximity between the porphyrin donor and the fullerene acceptor (Fig. 3).
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ChemInform Abstract: Preparation of Enantiomerically Pure C76 with a General Electrochemical Method for the Removal of Di(alkoxycarbonyl)methano Bridges from Methanofullerenes: The Retro-Bingel Reaction
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  • ChemInform
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
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