Charge separation in a covalently-linked phthalocyanine-oligo(p- phenylenevinylene)-C60 system. Influence of the solvent polarity

Article abstract of DOI:10.1016/j.jinorgbio.2011.11.011

A photo- and redoxactive system ZnPc-oPPV-C₆₀ 2, in which the photoexcited state electron donor - zinc phthalocyanine - and the ground state electron acceptor - C₆₀ - are connected by a oligo(p- phenylenevinylene) (oPPV) spacer, has been synthesized in a multi-step synthesis by means of two consecutive Wadsworth-Horner-Emmons and a dipolar 1,3-cycloaddition reactions as key steps. The simpler system ZnPc-C₆₀ 1 has also been prepared as a reference model for photophysical studies. In this regards, the photophysical investigations by means of fluorescence, flash photolysis, and transient-absorption spectroscopy have manifested a clear dependence between charge transfer kinetics and spatial arrangement. In both systems, intramolecular charge separation evolves from the photoexcited ZnPc and yields the ZnPc^?+/C₆₀^?- radical ion pairs. Interestingly, the ZnPc^?+/C₆₀ ^?- radical ion pair lifetimes and quantum yields are strongly impacted by the solvent polarity and the distance. To this end, maximum radical ion pair lifetimes of 2900 and 5530 ps were found in anisol for 1 and 2, respectively.

Full text of DOI:10.1016/j.jinorgbio.2011.11.011

Journal of Inorganic Biochemistry 108 (2012) 216–224
Contents lists available at SciVerse ScienceDirect
Journal of Inorganic Biochemistry
journal homepage: www.elsevier.com/locate/jinorgbio
Charge separation in a covalently-linked phthalocyanine-oligo
(p-phenylenevinylene)-C60 system. Influence of the solvent polarity
Juan-José Cid a,1, Axel Kahnt b,1, Purificación Vázquez a, Dirk M. Guldi b, Tomás Torres a,c,
⁎
a
Departamento de Química Orgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
b
Department of Chemistry and Pharmacy and Interdisciplinary Center for Molecular Materials, Friedrich-Alexander-Universität, Erlangen-Nürnberg, 91058 Erlangen, Germany
Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanociencia), Cantoblanco, 28049 Madrid, Spain
c
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 14 August 2011
Received in revised form 14 November 2011
Accepted 14 November 2011
Available online 22 November 2011
A photo- and redoxactive system ZnPc-oPPV-C60 2, in which the photoexcited state electron donor – zinc
phthalocyanine – and the ground state electron acceptor – C60 – are connected by a oligo(p-phenyleneviny-
lene) (oPPV) spacer, has been synthesized in a multi-step synthesis by means of two consecutive Wads-
worth–Horner–Emmons and a dipolar 1,3-cycloaddition reactions as key steps. The simpler system ZnPc-
C60 1 has also been prepared as a reference model for photophysical studies. In this regards, the photophysi-
cal investigations by means of fluorescence, flash photolysis, and transient-absorption spectroscopy have
manifested a clear dependence between charge transfer kinetics and spatial arrangement. In both systems,
Keywords:
Phthalocyanines
Fullerenes
Electron transfer
Photophysics
Artificial photosynthesis
intramolecular charge separation evolves from the photoexcited ZnPc and yields the ZnPc·+/C radical ion
·-
60
·-
pairs. Interestingly, the ZnPc·+/C radical ion pair lifetimes and quantum yields are strongly impacted by
60
the solvent polarity and the distance. To this end, maximum radical ion pair lifetimes of 2900 and 5530 ps
were found in anisol for 1 and 2, respectively.
© 2011 Elsevier Inc. All rights reserved.
1. Introduction
form long lived radical ion pair states. In this context, phthalocya-
nines (Pc) emerged as molecular building blocks for the implementa-
It is foreseeable that artificial photosynthetic systems that will ul-
timately power practical solar fuels production must be based on mo-
lecular and supramolecular assemblies [1]. In natural photosynthesis,
cascades of short range energy transfer and electron transfer process-
es occur between well arranged bioorganic dyes [2,3]. Therein, light
harvesting antenna molecules mostly based on chlorophyll capture
the light and transduce the excitation energy to the photosynthetic
reaction center. In order to mimetic natural photosynthesis on the
molecular level, the electron transfer in a large variety of bio-
inspired supermolecular and supramolecular systems in particular
based on chlorophyll [4,5], porphyrins [6–10], and phthalocyanines
[11–20] as electron donors and SWCNT (single wall carbon nano-
tubes) [1,21–23], fullerenes [24–27], quinones [28–31], and graphene
[32,33] as electron acceptors have already been widely investigated
by us and others.
tion as light harvesting antennas in solar energy conversion schemes.
Of particular importance is their great photostability due to the aro-
maticity of Pcs and their high extinction coefficients in the 700 nm
range allowing an effective utilization of the red part of the solar
spectrum.
Fullerenes as spherical carbon structure exhibit unique electron
acceptor properties. In particular, the small reorganization energy of
fullerenes in electron transfer reactions making it possible that the
charge separation occurs in the normal region of the Marcus parabola,
whereas the charge recombination is pushed deeply into the Marcus
inverted region. Keeping these features in mind, supramolecular
[34,35] and supramolecular [34,36–38] assemblies of ZnPc and C60
were synthesized and their photophysical properties investigated. In
all of the cases, charge separation from the first singlet excited state of
ZnPc to the fullerene yields one electron oxidized ZnPc·+ and the one
·-
A major goal in the development of the aforementioned systems is
to identify suitable candidates for solar device applications and to
gain a deeper understanding of photoinduced electron transfer pro-
cesses. It is, however, indispensable to develop electron-donor/accep-
tor systems that efficiently harvest the solar light and that efficiently
electron reduced C
.
60
Previous work has shown that the molecular architecture has a
tremendous impact on the yields and the lifetimes of the radical ion
pair states [34]. For example, in an electron-donor/acceptor conju-
gate, where ZnPc and C60 are directly linked to each other revealed
quantum yields for the radical ion pair state formation close to unity
in THF but the lifetimes were limited to 49 ps [39]. Implementing, on
the other hand, a spacer between both building blocks assisted in in-
creasing the radical ion pair state lifetime but at the costs of lower quan-
tum yields [39]. Investigating more complex structures such as a
⁎
Corresponding author at: Departamento de Química Orgánica, Facultad de Ciencias,
Universidad Autónoma de Madrid, E-28049 Madrid, Spain. Fax: +34 91497 3966.
E-mail address: tomas.torres@uam.es (T. Torres).
These authors contributed equally to the research.
1
0162-0134/$ – see front matter © 2011 Elsevier Inc. All rights reserved.
doi:10.1016/j.jinorgbio.2011.11.011

J.-J. Cid et al. / Journal of Inorganic Biochemistry 108 (2012) 216–224
217
N
H17C8
OC8H17
N
H17 C8
OC8H17
(H3C)3C
O
OC8H17
N
Zn
N
(H3 C)3C
O
N
N
N
N
N
N
N
N
N
N
N
1
2
N
N
Zn
C(CH3)3
(H3C)3C
N
C(CH3)3
(H3 C)3C
Fig. 1. Structures of phthalocyanine-based donor–acceptor systems ZnPc-C60 1 and ZnPc-oPPV-C60 2.
tripodal relay station of ZnPcs and C60 [40] or a bis-C60-bis-ZnPc [41] led
to no appreciable changes. For example, in the former case fairly long
radical ion pair state lifetimes of up to 1000 ps in benzonitrile were
seen to evolve with low quantum yields of 0.28. In the latter case, the
lifetimes are as short as 60 ps in anisole with quantum yields of only
0.46 what has been ascribed to the molecular arrangement of the
photoactive units, whose folding favors a closer spatial distance ZnPc–
a value of 0.62 [42]. Finally, a phenylene-vinylene (PV) linker led to
more balanced results — a lifetime of 2040 ps in anisole and a quantum
yield of 0.8 [42].
In the current contribution we wish to report on the synthesis and
photophysical characterization of two novel electron donor acceptor
conjugates. In these electron donor acceptor conjugates ZnPc and
C60 are linked via a heteroatom-containing linker in order to accelerate
C
60 than through the direct covalent bonds.
Considerable progress was made upon implementing a [2.2] para-
the charge separation and to slow down the charge recombination. One
electron-donor/acceptor conjugate contains a simple oxo-phenyl linker
between ZnPc and C60, whereas the other was linked with an oxo-bis-
PV linker (Fig. 1).
cyclophane linker between ZnPc and C60. Here, the radical ion pair
state lifetime in anisole is 26000 ps, while the quantum yield reaches
O
(H3C)3C
O
N
N
N
a)
Zn
N
N
N
1
N
N
C(CH3)3
(H3C)3C
3
O
OC8H1 7
OC8H1 7
OC8H17
(H3C)3C
O
N
Zn
N
b)
N
N
N
N
N
N
2
C(CH3)3
(H3C)3C
4
Scheme 1. Synthesis of 1 and 2. a) N-octylglycine, C60, toluene; 79%. b) N-octylglycine, C60, toluene; 29%.

218
J.-J. Cid et al. / Journal of Inorganic Biochemistry 108 (2012) 216–224
2. Results and discussion
2.1. Synthesis and characterization
benziodoxole-3(1H)-one-1-oxide) in dimethyl sulfoxide (DMSO), as
previously used by us [45], afforded formylphthalocyanine 6 in 74%
yield. The synthetic route for the synthesis of 6 proceeded through a
sequential two-steps Wadsworth–Horner–Emmons olefination
using tBuOK in dry THF. First, the reaction between formylphthalo-
cyanine 6 with 2,5-di-n-octyloxy-1,4-xylenebis(diethylphosphonate)
[47] gave compound 5a. In addition, the symmetrical compound
ZnPc-oPPV-ZnPc 5b was also obtained as a by-product in a non-
negligible amount (22%) [48]. In a second step, the reaction of 5
with 3-(diethoxymethyl)benzaldehyde afforded, after acidic treat-
ment, phthalocyaninic formyl derivative 4. In both reactions, trans-
isomers were obtained after chromatographic purification, in 42 and
47% yield, respectively. Finally in a last step, 1 and 2 were synthesized
from C60 and N-octylglycine in refluxing toluene with phthalocyani-
nic aldehydes 3 and 4, respectively. Isolation of the pure compounds
was accomplished by column chromatography in toluene/ethyl ace-
tate mixtures, eluting in second place after unreacted C60 and before
double condensation by-products (bis-adducts) in 79 and 29% yields,
respectively, as a mixture of unresolved regio- and enantiomers due
to the surrounding tert-butyl groups on the phthalocyaninic core and
the chiral center generated on the pyrrolidine ring, respectively.
All structures were confirmed by spectroscopic analyses (NMR,
FT-IR, UV–vis. and MS). 1H-NMR revealed for all phthalocyanine pre-
cursors signals in the form of multiplets between 9.8 and 6.0 ppm
corresponding to the aromatic protons. Alcohol 7 also exhibited a
split signal of the CH2OH group at around 5.3 ppm, while aldehyde
6 showed the signal of the formyl group at 9.7 ppm. In the 1H-NMR
The syntheses of 1 and 2 were accomplished by means of 1,3-cyclo-
addition reactions between C60 and the azomethine ylides generated in
situ upon condensation of N-octylglycine [43] with formylphthalocya-
nines 3 and 4, respectively (Scheme 1).
Phthalocyanine 3 was prepared following a procedure described
elsewhere [44], meanwhile unsymmetrical phthalocyanine 4 was
obtained by using a novel synthetic procedure starting from phthalo-
nitrile precursor 8 (Scheme 2).
To this end, phthalonitrile 8 was obtained from 4-(hydroxy)anisol
after a Mannich-like reaction with para-formaldehyde and morpho-
line, followed by alkylation with tosylate 13 [45] to give intermediate
11. Afterwards, a careful demethylation reaction with HBr, followed
by an ipso-substitution over 4-nitrophthalonitrile in basic media,
afforded phthalonitrile 9. The substitution, in a final step, of the mor-
pholine ring by an acetoxy group resulted in acetoxyphthalonitrile
precursor 8 in a 43% overall yield. Subsequently, the unsymmetrical
phthalocyanine 7 was prepared in 43% by a cyclotetramerization re-
action of 4-tert-butylphthalonitrile and phthalonitrile 8 in a 4:1
ratio in the presence of Zn(OAc)2 and refluxing dimethylaminoetha-
nol (DMAE). The desired phthalocyanine was separated chromato-
graphically as a mixture of regioisomers from the reaction mixture.
Next, an oxidation reaction of the hydroxyl group using a very soft ox-
idation with the periodinane derivative IBX [46] (1-hydroxy-1,2-
OH
OH
OC8H17
a)
b)
c)
N
N
O
O
O
O
O
12
11
OC8H17
OC8H17
O
OC8H17
N
O
d)
O
e)
f)
N
O
NC
NC
O
NC
NC
O
OH
9
8
10
OC8H17
OC8H17
O
P
OC8H17
OEt
OC8H17
OEt
R
(H3C)3C
(H3C)3C
O
O
N
N
Zn
N
N
N
N
N
N
N
N
i)
h)
N
Zn
N
N
4
N
N
N
C(CH3)3
(H3C)3C
C(CH3)3
(H3C)3C
5
7; R = CH2OH
g)
6; R= CHO
Scheme 2. Synthesis of phthalocyanine 4. a) anisol, p-formaldehyde, morpholine; 81%. b) (i) Cs2CO3, DMF, (ii) 13, DMF; 80%. c) (i) HBr (aq), (ii) CaCO3 (aq); 85%. d) 4-
nitrophthalonitrile, K2CO3, DMF; 92%. e) (Ac)2O, AcOH (glac.); 84%. f) 4-tert-butylphthalonitrile, Zn(AcO)2, DMAE; 43%. g) IBX, DMSO; 74%. h) 2,5-di-n-octyloxy-1,4-xylenebis(-
diethylphosphonate), t-BuOK, THF; 42%. i) (i) 3-(diethoxymethyl)benzaldehyde, t-BuOK, THF, (ii) HCl (aq) 0.1 M; 47%.

J.-J. Cid et al. / Journal of Inorganic Biochemistry 108 (2012) 216–224
219
spectrum of the phthalocyanine intermediate 5 the signal of the CH2-
P(O)(OEt)2 group appeared as a multiplet at around 4.5 ppm, while in
HMQC-NMR the signals of the vinylic protons show up between 6.9
and 6.8 ppm with a double bond coupling constant of 16.7 Hz. These
observations confirm the trans stereoselectivity of the Wadsworth–
Emmons reaction. Furthermore, in the 31P{H}-NMR spectrum the P
signals appeared at 26.0 ppm split in two, probably due to the regioi-
somers distribution. In FT-IR spectra, the νst(C_O) band in 6
appeared at around 1688 cm−1 and the νst(P_O) band in 5 at
1255 cm−1. Moreover, 4 and 5 showed the νoop(C=C-H) for trans
vinylenes at around 970 cm−1 [49]. Concerning the final products, the
1H-NMR spectra of 1 and 2 exhibited the signals that correspond to the
isoindol protons of the phthalocyanine core and the phenyl rings be-
tween 9.5 and 6.6 ppm. The three cyclic pyrrolidine signatures and
the one from the alkyl methylene attached to the nitrogen appeared be-
tween 5.4-4.0 and 3.6 ppm, respectively. In general, 2 showed more
split signals than 1 due to the higher complexity of its structure, the
number of regioisomers related to the double bond, and the aggregation
phenomena. In MS spectrometry (MALDI) also appeared for the titled
compounds the corresponding molecular peaks as M+ together with
Fig. 3. Fluorescence spectra of 1 in THF (solid line), 2 in THF (dashed line), and ZnPc
(dotted line) in toluene containing 1% pyridine at room temperature.
Transient absorption spectroscopy based on femtosecond and
nanosecond laser photolysis helped to provide spectroscopic and ki-
netic evidence of a charge transfer mechanism between photoexcited
peaks due to the loss of C60
.
2.2. Photophysical studies
ZnPc and C60.
The transient absorption changes of ZnPc relate to the first singlet
excited state of ZnPc showing a broad transient absorption maximiz-
ing around 490 and 800 nm, whereas a minimum at 680 nm corre-
lates with the bleaching of Q-band absorption of the ZnPc. This
transient decays via intersystem crossing to the first triplet excited
state showing a transient absorption maximum at 500 nm. The life-
time of the first singlet excited state obtained from a monoexponen-
tial fit of the decay at 800 nm is 3.1 ns — a value that agrees well with
previous reports [55,56].
When probing 1 and 2 the same singlet excited state characteris-
tics of ZnPc were found – despite the presence of the electron accept-
ing fullerene – upon photoexcitation. The ZnPc singlet excited state
features decay much faster in 1 and 2 compared to ZnPc and gave
rise to the formation of three new transient absorption bands maximiz-
ing at 520, 840, and 1000 nm (see Figs. 4 and 5). The maxima at 520 nm
and 840 nm are assigned to the one electron oxidized form of ZnPc
[57,58]. The maximum at 1000 nm, on the other hand, matches the ab-
sorption of the one electron reduced form of C60 [59,60].
In summary, transient absorption spectroscopy testifies the forma-
tion of radical ion pair states in 1 and 2. The lifetimes of these radical
ion pair states as obtained by fitting the decay of the 840 nm absorption
tend to be longer for 2 than for 1 — see Table 2.
Finally, the quantum yields of radical ion pair state formation were
determined in analogy to a previous description [39]. In particular,
the values ranged from as low as 0.46 in benzonitrile for 2 to as
high as 0.80 in THF for 1 — see Table 3.
The electronic ground state absorption spectra of 1 and 2 (see
Fig. 2) are essentially identical to that of ZnPc. In particular, a strong
maximum is seen around 685 nm, which is flanked by minor maxima
at 350 and 610 nm, which correspond to the Soret and Q-bands, re-
spectively [50,51]. An additional band is seen at around 250 nm,
which is a relatively good match for a C60 centered transition [52,53].
First inside into possible electron-donor–acceptor interactions,
that is, between ZnPc and C60 was lent from fluorescence assays. In
order to ensure comparable conditions solutions of 1, 2, and ZnPc
were adjusted to exhibit the same absorption of ca. 0.05 at the
610 nm excitation wavelength. For ZnPc, we recorded a fluorescence
spectrum that exhibits a strong *0-0 transition at 678 nm followed
by vibrational fine structure (i.e., *0-1, *0-2, etc.) at lower energies.
Important is the small energetic difference between the long-
wavelength absorption and short-wavelength fluorescence of only
5 nm, which speaks for the structural rigidity of ZnPc. The quantum
yields for the radiative pathway are 0.3 with an underlying lifetime –
measured in time-resolved measurements – of 3.1 ns [54]. In relation
to ZnPc, 1 and 2 revealed – see Fig. 3 and Table 1 – much lower fluo-
rescence quantum yields with values, for example, 0.011 in 1 and
0.089 in 2 in THF. This leads us to hypothesis that additional deactiva-
tion processes – either charge transfer or energy transfer – dictate the
excited state features of 1 and 2.
In variation to previously investigated ZnPc-C60 conjugates [39,40]
in polar and medium polar solvents (i.e., THF) the features of the rad-
ical ion pair state transform over time into those of the triplet excited
state centered at ZnPc. Spectroscopic support for this conclusion
came from a new transient absorption maximum at 500 nm — see
Fig. 6 [56]. Both, namely the radical ion pair state decay and the triplet
excited state formation are kinetically linked to each other. The triplet
quantum yields were determined by measuring the singlet oxygen
phosphorescence upon photoexcitation of oxygen saturated solutions
Table 1
Fluorescence quantum yields of 1 and 2 in solvents of different polarity.
1
2
Toluene
THF
Benzonitrile
0.033
0.011
0.004
0.064
0.089
0.059
Fig. 2. Absorption spectra of 1 (solid line) and 2 (dashed line) in THF at room
temperature.

220
J.-J. Cid et al. / Journal of Inorganic Biochemistry 108 (2012) 216–224
a)
c)
0.012
0.01
0.0025
0.002
0.008
0.006
0.004
0.002
0
0.0015
ΔOD
0.001
/ a.u.
ΔOD
/ a.u.
0.0005
0
-0.002
-0.004
-0.0005
400
600
800
1000
1200
0
500
1000
1500
2000
2500
3000
Wavelength / nm
Time / ps
0.007
0.006
0.005
0.004
0.003
0.002
0.001
0
b) 0.005
0.004
d)
0.003
ΔOD
/ a.u.
ΔOD
/ a.u.
0.002
0.001
0
-0.001
-0.001
0
500
1000
1500
2000
2500
3000
0
500
1000
1500
2000
2500
3000
Time / ps
Time / ps
Fig. 4. (a) Differential absorption spectra (visible and near-infrared) obtained upon femtosecond flash photolysis (670 nm–100 nJ) of 1 (~2.0×10−5 M) in argon saturated anisole
with time delays of 1 (filled circles) and 102 ps (open circles) at room temperature. (b) Time absorption profile at 840 nm of the spectra shown above, monitoring the charge sep-
aration and charge recombination in anisole. (c) Time absorption profile at 840 nm monitoring the charge separation and charge recombination in THF. (d) Time absorption profile
at 840 nm monitoring the charge separation and charge recombination in benzonitrile.
at 670 nm with ZnPc as a reference (i.e., 0.7). Quantum yields for 1
were 0.79 in toluene and 0.18 in THF, while for 2 the values were
0.79 in toluene and 0.29 in THF.
harmonics (i.e., 355 nm) coming from a Nd:YAG laser (Brilliant,
Quantel). Pulse widths of b5 ns with an energy of 10 mJ were select-
ed. The optical detection is based on a pulsed (MSP 05, Müller
Elektronik-Optik) xenon lamp (XBO 450, Osram), a monochromator
(Spectra Pro 2300i, Acton Research), a R928 photomultiplier tube
(Hamamatsu Photonics), a Nano 5 InGaAs photodiode (Coherent)
and a 1 GHz digital oscilloscope (WavePro7100, LeCroy). The laser
power of every laser pulse was registered using a bypath with a fast
silicon photodiode. The solvents were always of spectroscopic grade.
The ns-laser photolysis experiments were performed using 1 cm
quartz cells and the solutions were saturated with argon. The femto-
second transient absorption measurements were carried out with a
CPA-2101 femtosecond laser (Clark MXR). The excitation wavelength
was generated with a NOPA (Clark MXR). The laser output energy
was 100 nJ per pulse.
3. Conclusions
In summary, we have succeeded in the syntheses of two novel
ZnPc-C60 electron donor acceptor conjugates bearing different linkers
that both contain an oxygen atom. In addition, we have confirmed the
efficient formation of long-lived radical ion pairs, that is, ZnPc·+-C
.
·-
60
Most important is the fact that the incorporation of n orbitals-
containing heteroatoms (i.e., oxygen) facilitates, on one hand, the
charge separation, but slows down, on the other hand, the energy
wasting charge recombination. Surprisingly high are the quantum
yields of charge separation with values of 0.8 and 0.79 in THF and
benzonitrile, respectively, for 1.
4.2. Experimental part
4. Materials and methods
4.2.1. 9,16,23-Tri-tert-butyl-2-{4′-[(3″-N-n-octyl)-[60]fulleropyrrolidin-
2″-yl]phenoxy}phthalocyaninato zinc(II)} (regioisomers mixture) (1)
C60 fullerene (255 mg, 0.354 mmol) and N-octylglycine (113 mg,
0.606 mmol) were dissolved in dry toluene (40 mL) in an ultrasounds
bath. To this solution, a well-stirred solution of phthalocyanine 3
(100 mg, 0.101 mmol) in dry toluene (20 mL) was added dropwise.
Afterwards, the mixture was refluxed for 18 h in an argon atmo-
sphere. When cooled, the solvent was vacuum-evaporated affording
a brown-greenish residue. The desired compound was purified from
the crude on a chromatographic column on silica gel (SiO2) using a
4.1. Photophysics
Optical absorptions were measured with a Cary 5000 UV/Vis–NIR
spectrometer (Varian). Such measurements, with the exception of
the femtosecond photolysis experiments, were carried out using
quartz cells with a 1 cm optical path length. Steady-state fluorescence
measurements were performed by using a Fluoromax P (Horiba Jobin
Yvon). Transient absorption experiments – based on nanosecond
laser photolysis – were performed with the output of the third

J.-J. Cid et al. / Journal of Inorganic Biochemistry 108 (2012) 216–224
221
Table 3
a)
Radical ion pair state quantum yields of 1 and 2 in solvents of different polarity.
0.001
0.002
0
1
2
Anisole
THF
Benzonitrile
0.56
0.80
0.79
0.55
0.50
0.46
ΔOD
/ a.u.
ethyl acetate (3:2) as eluent, yielding 12 (1.46 g, 81%) as an yellow-
orangish oil. 1H-NMR (200 MHz, CDCl3), δ=9.87 (br s, 1H; ArOH),
6.77-6.74 (m, 2H, H-3, H-5), 6.56 (br d, 1H; H-2), 3.75 [br t, 4H;
N(CH2)2(CH2)2O], 3.74 (s, 3H; ArOCH3), 3.66 (s, 1H; ArCH2N), 2.56 [br
t, 4H; N(CH2)2(CH2)2O]. 13C-NMR (75 MHz, CDCl3), δ=152.6 (C-4),
151.2 (C-1), 121.3 (C-2), 116.5 (C-6), 114.7 (C-3), 113.8 (C-5), 66.7
(NCH2CH2O), 61.9 (ArOCH3), 55.7 (ArCH2N), 52.9 (NCH2CH2O). MS
(EI): m/z=223 [M]+ (87%), 208 M1 [M-CH3]+ (7%), 136 M2 [M-
C4H8NO]+ (100%), 108 M3 [M1-C5H10NO]+ (29%), 86 [C4H8NO]+ (67%).
-0.002
-0.004
400
600
800
1000
3000
Wavelength / nm
b)
0.0025
0.002
0.0015
0.001
0.0005
0
4.2.3. 1-(2-Ethylhexyloxy)-4-methoxy-2-(morpholino-N-methyl)benzene
(11)
Compound 12 (1.40 g, 6.27 mmol) and Cs2CO3 (6.13 g,
18.81 mmol) in dry DMF (75 mL) were heated at 70 °C under argon
atmosphere for 15 min. Subsequently, a solution of sulphonate deriv-
ative 13 (2.00 g, 7.00 mmol) in dry DMF (5 mL) was added dropwise.
Then, the reaction was brought to 55 °C and stirred for 6 h. After cooling
down at room temperature, the mixture was poured into brine
(300 mL) and extracted with diethyl ether (4×50 mL). The organic ex-
tract was dried over Na2SO4, filtered and the solvent eliminated in
ΔOD
/ a.u.
-0.0005
0
500
1000
1500
2000
2500
3000
a) 0.05
Time / ps
Fig. 5. (a) Differential absorption spectra (visible and near-infrared) obtained upon
femtosecond flash photolysis (670 nm–100 nJ) of 2 (~2.0×10−5 M) in argon saturated
anisole with time delays of 1 (filled circles) and 102 ps (open circles) at room temper-
ature. (b) Time absorption profile at 840 nm monitoring the charge separation and
charge recombination in THF.
0
ΔOD
-0.05
/ a.u.
gradient of polarity, from toluene to toluene/ethyl acetate (20:1) as
eluent. In this way, 1 137 mg (79%) was obtained as dark green
solid. Mp: >250 °C. 1H-NMR (500 MHz, THF-d6), δ=9.5-8.7 (m, 8H;
PcH), 8.2-8.0 (m, 4H; PcH), 8.0-7.3 (m, 4H; ArH), 5.38 (m, 1H;
CHNCH2), 4.98 (m, 1H; CHNCH2), 4.09 (m, 1H; CHNCH2), 3.37 (m,
2H, NCH2), 2.3-0.8 [m, 42H, (CH2)6CH3, C(CH3)3]. UV–vis (THF),
λmax (log ε)=673 (5.4), 608 (4.6), 348 (5.0), 240 (5.1)nm. MS
-0.1
-0.15
300
400
500
600
700
800
900
Wavelength / nm
(MALDI, dithranol), m/z=1717–1709 [M]+ (42%), 996–989 [M-
+
C60
]
(100%). HRMS (MALDI-TOF, dithranol): calc. for
b) 0.03
C120H63N9OZn: 1709.44812, found: 1709.44415.
0.025
4.2.2. 4-Methoxy-2-(morpholino-N-methyl)phenol (12)
0.02
A mixture of anisol (1.00 g, 8.06 mmol), p-formaldehyde (242 mg,
8.42 mol) and morpholine (702 mg, 8.06 mol) in benzene (22 mL)
was refluxed in a Dean–Stark equipped set for 18 h. After cooling,
the solvent was vacuum-evaporated affording a dark oily orangish
residue. The crude was dissolved in CHCl3, washed with water
0.015
0.01
ΔOD
/ a.u.
0.005
0
(4×60 mL),
a 10% bisulphite solution (2×50 mL) and brine
(2×50 mL). After drying over Na2SO4, the solvent was eliminated
and the crude subjected to chromatography on silica gel with toluene/
-0.005
0
50
100
150
Table 2
Time / μs
Radical ion pair state lifetimes of 1 and 2 in solvents of different polarity.
1
2
Fig. 6. (a) Differential absorption spectra (visible and near-infrared) obtained upon
nanosecond flash photolysis (355 nm) of 2 (~1.3×10−5 M) in argon saturated toluene
with a time delays of 2 μs at room temperature. (b) Time absorption profile at 500 nm
of the spectrum shown above, monitoring the decay of the triplet first excited state in
toluene.
Anisole
THF
Benzonitrile
2900 ps
890 ps
220 ps
5530 ps
3410 ps
230 ps

222
J.-J. Cid et al. / Journal of Inorganic Biochemistry 108 (2012) 216–224
vacuum. The pure compound was isolated from the brown oily residue
by column chromatography (SiO2) passing from hexane/ethyl acetate
(1:1) into ethyl acetate. Following this procedure compound 11
(1.69 g, 80%) afforded as an orangish oil. 1H-NMR (200 MHz, CDCl3),
δ=6.97 (d, Jm,3–5=2.9 Hz, 1H; H-3), 6.79 (d, Jo,5–6=8.7 Hz, 1H; H-6),
6.73 (dd, Jo,5–6=8.7, Jm,3–5=2.9 Hz, 1H; H-5), 3.79 (d, J=5.1 Hz, 2H;
ArOCH2), 3.77 (s, 3H; ArOCH3), 3.71 [br t, J=4.6 Hz, 4H;
N(CH2)2(CH2)2O], 3.53 (s, 2H; ArCH2N), 2.50 [m, J=4.6 Hz, 4H;
N(CH2)2(CH2)2O], 1.70 (st, J=5.8 Hz, 1H; ArOCH2CH), 1.58-1.22 [m,
8H; (CH2)4], 0.92 (t, J=7.6 Hz, 3H; CH3), 0.87 (t, J=6.6 Hz, 3H; CH3).
13C-NMR (75 MHz, CDCl3), δ=153.3 (C-4), 151.8 (C-1), 127.4 (C-2),
116.5 (C-6), 112.4 (C-3), 112.3 (C-5) 71.0 (ArOCH2), 67.1 (NCH2CH2O),
56.5 (ArOCH3), 55.7 (ArCH2N), 53.6 (NCH2CH2O), 39.7 (ArOCH2CH),
30.7 (CH2), 29.1 (CH2), 24.1 (CH2), 23.1 (CH2), 14.1 (CH3), 11.2 (CH3).
801, 766, 522 cm−1. MS (EI): m/z=447 [M]+ (13%), 348 M1 [MH-
+
C5H10NO+
]
(78%), 335 M2 [MH-C8H17
]
(66%), 249 M3 [M2-
C4H8NO]+ (62%), 100 M4 [C5H10NO]+ (28%), 86 M6 [C4H8NO]+
(100%).
4.2.6. 2-(2-Ethylhexyloxy)-5-(3,4-dicyanophenoxy)benzyl acetate (8)
Derivative 9 (2.52 g, 5.63 mmol) was reacted in a mixture of acetic
anhydride (53 mL) and glacial acetic acid (13 mL) under argon atmo-
sphere for 14 h. When consumption of starting compound was com-
plete, the solvents were evaporated and the residue dissolved in
chloroform and washed with water (100 mL each). The organic extract
was further washed with a solution of hydrochloric acid (0.1 M,
3×60 mL), neutralized with a saturated sodium bicarbonate solution
(2×50 mL), washed with brine (2×50 mL) and dried over MgSO4. The
drier agent was removed by filtration and the chloroform evaporated
under reduced pressure to leave a slurry brown oily, which was purified
by column chromatography on silica using toluene/ethyl acetate (4:1)
as eluent to give 8 (2.00 g, 84%) as a pale yellow oil that solidified by
standing. Mp: 55–56 °C. 1H NMR (200 MHz, CDCl3): δ=7.70 (d,
Jo,5–6=9.7 Hz, 1H; H-6), 7.23 (dd, Jo,5–6=9.7 Hz, Jm,3–5=2.6 Hz, 1H, H-
5), 7.19 (d, Jm,3–5=2.6 Hz, 1H; H-3), 7.05 (br s, 1H; H-2′), 6.97 (br d ,
1H; H-6′), 6.94 (br d ,1H; H-5′), 5.15 [s, 2H; ArCH2OC(O)CH3], 3.91 (d,
J=5.4 Hz, 2H; ArOCH2), 2.10 [s, 3H: OC(O)CH3] 1.76 (st, J=6.5 Hz,
1H; ArOCH2CH) 1.64-1.23 [m, 8H; (CH2)4], 0.95 (t, J=7.0 Hz, 3H; CH3)
0.91 (t, J=5.6 Hz, 3H; CH3). 13C-NMR (75 MHz, CDCl3): δ=170.8
(OC(O)CH3), 162.6 (C-4), 155.1 (C-1′), 146.2 (C-4′), 135.5 (C-6), 127.0
(C-3′), 121.6 (C-5), 121.3 (C-3), 121.1 (C-2), 121.0 (C-2′), 117.6 (C-6′),
115.6 (CN), 115.2 (CN), 112.5 (C-5′), 108.5 (C-1), 70.9 (ArOCH2), 61.3
(ArCH2OC(O)CH3), 39.5 (ArOCH2CH), 30.7 (CH2), 29.2 (CH2), 24.0
(CH2), 23.1 (CH2), 21.0 (ArCH2OC(O)CH3), 14.2 (CH3), 11.3 (CH3). FT-
IR (KBr): ν=2932, 2867, 2231 νst(C≡N), 1738 νst(C=O), 1610, 1588,
1566, 1486, 1451, 1427, 1413, 1379, 1362, 1314, 1278, 1237 νas(C-O),
1204, 1166, 1147, 1121, 1085, 1046, 1011, 969, 945, 918, 900, 852,
827, 774, 651, 526, 464, 443, 426 cm−1. MS (EI): m/z=420 [M]+
MS (EI): m/z=335 [M]+ (22%), 250 M2 [MH-C4H8NO]+ (24%),
+
236 M3 [MH-C5H10NO]+ (43%), 223 M4 [MH-C8H17
]
(50%), 137 M5
[C8H17]
+ (100%), 86 M6 [C4H8NO]+ (68%).
4.2.4. 4-(2-Ethylhexyloxy)-3-(morpholino-N-methyl)phenol (10)
A heterogeneous mixture of 11 (3.30 g, 9.84 mmol) in a 45% aque-
ous solution of HBr was heated at 95 °C for 4 h. Once demethylation
was complete, the mixture was cooled at 0 °C and a saturated solution
of CaCO3 was added drop by drop until pH=9.0. Then, the suspen-
sion was poured into water (100 mL) and extracted with AcOEt
(3×50 mL), dried over Na2SO4 and the solvent vacuum-eliminated
after filtering. The oily brownish residue was purified by column
chromatography on silica gel using toluene/ethyl acetate (1:1) as el-
uent, affording 10 (2.69 g, 85%) as an orangish oil. 1H-NMR
(200 MHz, CDCl3), δ=6.88 (d, Jm =2.7 Hz,1H; H-2), 6.74 (d,
Jo =8.1 Hz, 1H; H-5), 6.67 (dd, Jm =2.7 Hz, Jo =8.1 Hz, 1H; H-6),
3.78 (d, J=5.4 Hz, 2H; ArOCH2), 3.72 [br t, J=4.8 Hz, 4H;
N(CH2)2(CH2)2O], 3.51 (s, 1H; ArCH2N), 2.51 [m, 4H; N(CH2)2(CH2)2O],
1.68 (st, J=8.9 Hz, 1H; ArOCH2CH), 1.55-1.20 [m, 8H; (CH2)4], 0.92 (t,
J=7.5 Hz, 3H; CH3), 0.90 (t, J=4.5 Hz, 3H; CH3). MS (EI): m/z=321
+
[M]+ (23%), 222 M3 [MH-C5H10NO]+ (60%), 209 M4 [MH-C8H17
]
(10%), 308 M1 [MH-C8H17]
+ (9%), 248 M2 [M1-C2H3O2]+ (100%).
(63%), 123 M5 [M4-C4H8NO]+ (92%), 86 M6 [C4H8NO]+ (100%).
4.2.7. 9,16,23-Tri-tert-butyl-2-[4-(2-ethylhexyloxy)-3-(hydroxymethyl)]
phenoxyphthalocyaninato zinc(II) (regioisomers mixture) (7)
4.2.5. 4[4-(2-Ethylhexyloxy)-3-(morpholino-N-methyl)phenoxy]
phthalonitrile (9)
Phthalonitrile 8 (200 mg, 0.48 mmol), 4-tert-butylphthalonitrile
(351 mg, 1.90 mmol) and Zn(AcO)2 (106 mg, 0.55 mmol) were stir-
red in DMAE (4 mL) and refluxed under argon atmosphere for 20 h.
Then, the solution was cooled down and methanol (20 mL) was
added. The mixture was refluxed again for further 2 h, and after cool-
ing, poured into water (100 mL). The blue precipitate was collected
by filtration through celite®. The resulting dark blue solid was
washed with water, mixtures methanol/water (1:2) and (1:1)
(100 mL each), and methanol (50 mL). Afterwards, the solid was
dried and redissolved in tetrahydrofuran and purified by column
chromatography (SiO2) using hexane/dioxane (3:1) as eluent. The
isolated blue solid obtained was triturated in hot hexane, filtered
and dried to afford phthalocyanine 7 (202 mg, 43%) as a dark blue
solid. Mp: >250 °C. 1H NMR (500 MHz, CDCl3): δ=9.5-8.4 (m, 8H;
PcH), 8.3-7.4 (m, 4H; PcH), 7.1-6.0 (m, 3H, ArH), 5.4-5.1 (m, 2H;
ArCH2OH), 4.0-3.7 (m, 2H; ArOCH2), 2.2-0.6 [m, 42H; CH, CH2, CH3,
C(CH3)3]. UV–vis (THF): λmax (log ε)=674 (4.9), 608 (4.1), 348
(4.4), 286 (4.0)nm. MS (MALDI, dithranol): m/z=1002–994. Anal.
Calcd (%) for C59H62N8O3Zn: C, 70.20; H, 6.28; N, 10.92. Found: C,
70.15; H, 6.21; N, 11.00.
4-Nitrophthalonitrile (596 mg, 3.44 mmol), K2CO3 (1.38 g,
10.00 mmol) and 10 (920 mg, 2.86 mmol) in dry DMF (45 mL) were
heated at 50 °C under an argon atmosphere for 66 h. After cooling
down to room temperature, the mixture was poured into 300 mL of
brine and extracted with diethyl ether (5×50 mL). The organic ex-
tracts were joined, washed with solutions of sodium hydroxide
(0.1 M, 2×50 mL), sodium bicarbonate (2×50 mL) and brine
(2×50 mL) and dried over magnesium sulfate. After filtration, the
solvent was evaporated giving a yellow oily crude. Compound 9 was
isolated on a chromatographic column (SiO2) using toluene/ethyl ac-
etate as eluent, affording (1.18 g, 92%) as viscous yellow oil that solid-
ified by standing. Mp: 39–41 °C. 1H-NMR (300 MHz, CDCl3): δ=7.70
(d, Jo,5–6 =9.7 Hz, 1H; H-6), 7.22 (dd, Jo,5–6 =9.7 Hz, Jm,2–6 =2.2 Hz,
1H; H-5), 7.19 (d, Jm,2–6 =2.2 Hz, 1H; H-3), 7.13 (br s, 1H; H-2′),
6.90 (br d, 2H; 5′-H, 6′-H), 3.88 (d, J=4.8 Hz, 2H; ArOCH2), 3.70 [br
t, 4H; N(CH2)2(CH2)2O], 3.55 (s, 2H; ArCH2N), 2.49 [br t, 4H;
N(CH2)2(CH2)2O], 1.76 (st, 1H; ArOCH2CH), 1.64-1.23 [m, 8H, (CH2)4],
0.95 (t, J=7.0 Hz, 3H; CH3), 0.92 (t, J=6.5 Hz, 3H; CH3). 13C-NMR
(75 MHz, CDCl3): δ=162.6 (C-1′),155.5 (C-1), 146.3 (C-4), 135.3 (C-
5′),129.0 (C-6′),122.3 (C-2′),121.0 (C-2), 120.8 (C-3), 119.8 (C-5),
117.5 (CN), 115.5 (CN), 115.0 (C-3′), 112.5 (C-6), 108.3 (C-4′), 70.8
(ArOCH2), 67.0 (N(CH2)2(CH2)O), 56.1 (N(CH2)2(CH2)O), 53.7
(ArCH2N), 39.5 (ArOCH2CH), 30.7 (CH2), 29.1 (CH2), 24.1 (CH2), 23.0
(CH2), 14.0 (CH3), 11.2 (CH3). FT-IR (KBr): ν=2958, 2929, 2860,
2806, 2600, 2232 νst(C≡N), 1591, 1562, 1489, 1420, 1396, 1383,
1353, 1335, 1298, 1247, 1199, 1172, 1150, 1114, 1086 νas(C-O-C),
1072, 1035, 1010, 975, 930, 911, 891 νs(C-O-C), 867, 839, 826,
4.2.8.
9,16,23-Tri-tert-butyl-2-[4-(2-ethylhexyloxy)-3-formyl]
phenoxyphthalocyaninato zinc(II) (regioisomers mixture) (6)
To a well stirred and colorless solution of periodinane 1-hydroxy-
1,2-benziodoxole-3(1H)-one-1-oxide (IBX) (90 mg, 0.321 mmol) in
dimethyl sulfoxide (45 mL), compound 7 (200 mg, 0.201 mmol) was
added at once. The solution was stirred at room temperature for 5 h.
and then, poured over brine (200 mL) and extracted with diethyl

J.-J. Cid et al. / Journal of Inorganic Biochemistry 108 (2012) 216–224
223
ether (3×50 mL). The organic layer was separated, washed with a
saturated solution of sodium bicarbonate (2×60 mL), brine
(2×60 mL) and dried over sodium sulfate. After filtration of the
drier agent, the solvent was evaporated and the blue solid was puri-
fied by a short column chromatography on silica gel using hexane/di-
oxane (4:1) as eluent, affording aldehyde 6 as dark blue solid
(147 mg, 74%). Mp: >250 °C. 1H NMR (500 MHz, CDCl3): δ=9.9-9.5
(br s, 1H; CHO), 8.9-8.0 (m, 8H; PcH), 8.0-7.4 (m, 4H; PcH), 7.4-6.3
(m, 3H; ArH), 4.0-3.7 (br d, 2H; ArOCH2), 2.1-0.7 [m, 42H; CH, CH2,
CH3, C(CH3)3]. FT-IR (KBr): ν=2959, 2918, 2864, 1688 νst(C=O),
1620, 1493, 1425, 1398, 1331, 1290, 1263, 1233, 1128, 1008, 1047,
926, 831, 752, 698, 540, 444 cm−1. UV–vis (CHCl3): λmax (log ε)=
673 (5.0), 607 (4.3), 350 (4.6) nm. MS (MALDI, dithranol):
m/z=1000–992. Anal. Calcd (%) for C59H60N8O3Zn: C 71.25; H 6.08;
N 11.27. Found: C 71.29; H 6.12; N 11.28.
dithranol): m/z=1461–1453. HRMS (MALDI-TOF, dithranol): calc.
for C91H104N8O5Zn: 1452.7424, found: 1452.7416.
4.2.11. 9,16,23-Tri-tert-butyl-2-{[4′-(2-ethylhexyloxy)-3′-[(E)-
vinylen-2″,5″-bis(n-octyloxy)-4″-{(E)-vinylen-3″′-[3″′-(N-n-octyl)-[60]
fulleropyrrolidin-2″′-yl]fenil}fenil]fenoxi}phthalocyaninato zinc(II) (regioi
somers mixture) (2)
C60 fullerene (46 mg, 0.063 mmol) and N-octylglycine (24 mg,
0.126 mmol) were dissolved in dry toluene (12 mL) in an ultrasounds
bath. To this solution, a well-stirred solution of phthalocyanine 6
(30 mg, 0.021 mmol) in dry toluene (8 mL) was added dropwise. Af-
terwards, the mixture was refluxed for 18 h in an argon atmosphere.
After cooling down, the solvent was vacuum-evaporated affording a
brown-greenish residue. The desired compound was purified from
the crude on a chromatographic column (SiO2) using a polarity gradi-
ent, passing from toluene to toluene/ethyl acetate (1:1). Following
this procedure, 2 (14 mg, 29%) was obtained as dark green solid.
Mp: >250 °C. 1H NMR (500 MHz, CDCl3): δ=9.5-6.6 (m, 25H; PcH,
ArH, Ar-CH=CH-Ar′), 5.33 (d, 1H; CHNCH2), 5.2-4.7 (m, 2H;
CHNCH2), 4.2-3.8 (m, 6H, ArOCH2), 3.8-3.5 (m, 2H; NCH2), 2.1-0.6
[m, 87H, CH, CH2, CH3, C(CH3)3]. UV–vis (THF): λmax (log ε)=681
4.2.9. 9,16,23-Tri-tert-butyl-2-{[4′-(2-ethylhexyloxy)]-3′-[(E)-vinylen-4″-
(diethylmethylphosphonate)-2″,5″-bis(n-octyloxy)]}phthalocyaninato
zinc(II) (regioisomers mixture) (5)
To
0.121 mmol) and bis-phosphonate (230 mg, 0.362 mmol) in dry
THF (20 mL), suspension of potassium tert-butoxide (20 mg,
a well-stirred solution of phthalocyanine 6 (120 mg,
(4.8), 614 (4.0), 406 (sh) (4.3), 330 (4.8), 259 (5.1)nm. MS (MALDI,
a
+
dithranol): m/z=2308–2298 [M]+ (35%), 1586–1578 [M-C60
]
0.182 mmol) in dry THF (6.0 mL) was added drop by drop in an
argon atmosphere. The reaction was allowed to react at the same
temperature for 3 h, after which the solvent was evaporated in vacu-
um. The crude was subjected to a chromatographic column (SiO2) in
hexane/dioxane (3:1) as eluent, affording 5 (75 mg, 42%) as a blue-
greenish solid. Mp: >250 °C. 1H NMR (500 MHz, CDCl3): δ=9.6-9.1
(m, 7H; PcH), 8.8-8.6 (m, 1H; PcH), 8.3-8.2 (m, 3H; PcH), 7.66
(br s, 1H; ArH), 7.30 (br s, 1H; ArH), 7.1-7.0 (d, 1H; ArH), 6.90 (d,
Jtrans =16.7 Hz 1H; Ar-CH=CH-Ar′), 6.80 (d, Jtrans =16.7 Hz 1H;
Ar-CH=CH-Ar′), 6.27 (d, 1H; ArH), 4.8-4.3 (m, 2H; ArCH2P), 4.2-
3.7 (br s, 6H; ArOCH2), 3.6-3.2 [m, 4H; P(O)(OCH2CH3)2], 2.1-0.4
[m, 82H; CH(CH2)4CH3, P(O)(OCH2CH3)2, CH, CH2, C(CH3)3]. 31P
NMR (202 MHz, CDCl3): δ=25.99, 26.03. FT-IR (KBr): ν=2951,
2920, 2854, 1610, 1487, 1464, 1404, 1388, 1361, 1328, 1263, 1255
(100%), 1000–992 [M-(C83H109N8O2Zn)-(3xC8H17)]+ (75%). HRMS
(MALDI-TOF, dithranol): calc. for
found: 2297.8984.
C160H123N9O4Zn: 2297.9021,
Abbreviations
t-BuOK Potassium tert-butoxide
Dithranol 1,8,9-Anthracenetriol
DMF
DMAE
EI
N,N-Dimethylformamide
Dimethylaminoethanol
Electron Impact
IBX
HMQC
HRMS
1-Hydroxy-1,2-benziodoxole-3(1H)-one-1-oxide
Heteronuclear Multiple Quantum Correlation
High Resolution Mass Spectrometry
νst(P=O), 1215, 1198, 1147, 1088, 1045 νst(P-O), 969 νδ
oop
MALDI Matrix-Assisted Laser Desorption Ionization
(C=C-H trans), 920, 827 νst(P-O), 746, 669, 671 cm− 1. UV–vis
(THF): λmax (log ε)=680 (5.1), 613 (4.3), 349 (4.8) nm. MS
(MALDI, dithranol): m/z=1481–1473 [M]+ (37%), 1000–992
[M-(P(O)(OEt)2-(3xC8H17)]+ (12%). HRMS (MALDI-TOF, dithra-
nol): calc. for C87H109N8O7PZn: 1472.7474, found: 1472.7443.
Mp
MPc
MS
oPPV
Pc
Melting Point
Metallophthalocyanine
Mass Spectrometry
Oligo(p-phenylenevinylene)
Phthalocyanine
PV
Phenylene-vinylene
SWCNT Single wall carbon nanotubes
4.2.10. 9,16,23-Tri-tert-butyl-2-{[4′-(2-ethylhexyloxy)-3′-{(E)-vinylen-
2″,5″-bis(n-octyloxy)-4″-[(E)-vinylen-3″′-(formil)]fenil}fenil]fenoxi}]
phthalocyaninato zinc(II) (regioisomers mixture) (4)
THF
TLC
TMS
TOF
Tetrahydrofuran
Thin Layer Chromatography
Tetrametylsilane
To a well-stirred solution of compound 5 (58 mg, 0.039 mmol)
and 3-(diethoxymethyl)benzaldehyde (16 mg, 0.077 mmol) in dry
THF (6 mL), a suspension of t-BuOK (16 mg, 0.143 mmol) in dry THF
(1.5 mL) was added drop by drop in an argon atmosphere. The reac-
tion was allowed to react at the same temperature for 2 h, after
which a 0.1 M HCl (5 mL) solution was added dropwise. The mixture
was stirred for 30 min. and then extracted with Et2O (2×30 mL). The
organic extracts were joined, washed with a saturated solution of
NaHCO3 (2×30 mL) and dried over Na2SO4. After evaporation of the
solvent at reduced pressure, the dark green crude was purified on a
chromatographic column (SiO2) in hexane/dioxane (3:1) as eluent,
resulting 4 (27 mg, 47%) as a blue-greenish solid. Mp: >250 °C. 1H
NMR (500 MHz, THF-d8): δ=9.7-9.5 (m, 1H; CHO), 9.5-8.8 (m, 8H;
PcH), 8.3-8.1 (m, 4H; PcH), 8.0-6.5 (m, 13H; ArH, Ar-CH=CH-Ar′),
4.0-3.4 (m, 6H; ArOCH2), 2.0-0.6 [m, 72H; CH, CH2, C(CH3)3]. FT-IR
(KBr): ν=2966, 2926, 2858, 1709 νst (C=O), 1612, 1493, 1425,
Time-Of-Flight
UV–vis Ultraviolet–visible
Acknowledgments
This work has been supported by the Spanish MICINN and MEC
(CTQ2011-24187/BQU and CONSOLIDER INGENIO 2010, CSD2007-
00010 Nanociencia Molecular, PLE2009-0070), and the Comunidad
de Madrid (MADRISOLAR-2, S2009/PPQ/1533). Financial support by
Fonds der Chemischen Industrie (FCI), Deutsche Forschungsge-
meinschaft (SFB 583: Redoxaktive Metallkomplexe — Reaktivitäts-
steuerung durch molekulare Architekturen), and Exzellenzcluster
EAM-Engineering of Advanced Materials is also acknowledged.
Appendix A. Supplementary data
1398, 1333, 1254, 1227, 1146, 1092, 1051, 976 νδ
(C=C-H
oop
trans), 928, 833, 752, 692, 530, 461 cm−1. UV–vis (THF): λmax (log
ε)=680 (5.0), 613 (4.4), 407 (sh) (4.5), 348 (4.7)nm. MS (MALDI,
Supplementary data to this article can be found online at doi:10.
1016/j.jinorgbio.2011.11.011.

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