Extended benzodifuran-furan derivatives as example of π-conjugated materials obtained from sustainable approach

Article abstract of DOI:10.1016/j.tet.2012.07.079

The synthesis of extended benzodifuran-furan systems are described as an example of π-conjugated materials prepared by following a green approach with only water being produced as waste and using furan derivatives from renewable sources. Investigation of their optical and electrochemical properties shows that the new compounds present electronic properties compatible for application in organic electronics.

Full text of DOI:10.1016/j.tet.2012.07.079

Tetrahedron 68 (2012) 8617e8621
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Tetrahedron
journal homepage: www.elsevier.com/locate/tet
Extended benzodifuranefuran derivatives as example of
p
-conjugated materials
obtained from sustainable approach
*
ꢀ ꢀ
ꢁ
Chady Moussallem, Frederic Gohier, Charlotte Mallet, Magali Allain, Pierre Frere
ꢀ
ꢀ
LUNAM Universite, Universite d’Angers, MOLTECH-Anjou UMR CNRS 6200, SCL group, 2 Boulevard Lavoisier, 49045 Angers cedex, France
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 3 April 2012
Received in revised form 19 July 2012
Accepted 24 July 2012
Available online 1 August 2012
The synthesis of extended benzodifuranefuran systems are described as an example of
p-conjugated
materials prepared by following a green approach with only water being produced as waste and using
furan derivatives from renewable sources. Investigation of their optical and electrochemical properties
shows that the new compounds present electronic properties compatible for application in organic
electronics.
Ó 2012 Elsevier Ltd. All rights reserved.
Keywords:
Conjugated materials
Organic semiconductors
Furan derivatives
Green chemistry
1. Introduction
conjugated structures via synthetic pathways, such as Knoevenagel
condensation19,23,24 or Schiff base reactions25e27 leading only to
The development of
p
-conjugated materials is motivated by
water as waste. Hence, the formation of ethylenic or the iso-
electronic azomethine bonds (eC]Ne) to lengthen the conjugated
systems by clean reactions between aldehydes and carbanions or
amines contrast with the Wittig or Wittig Horner reactions, which
produce phosphine oxide or phosphate derivatives as waste.
In this context, we have focused on the synthesis via green
their potential technological applications as organic semi-
conducting materials for the fabrication of (opto)electronic de-
vices, such as field-effect transistors (OFET), electroluminescent
diodes (OLED) and photovoltaic cells.1e4 The major goal in the de-
velopment of organic-based electronic devices resides in the low
cost process for their fabrication by using spin coating or inkjet
printing.5e8 On the other hand, the flexibility of the organic
chemistry approach of p-donors Iaec composed of a benzodifuran
moiety connected to furan units by azomethine junctions (Fig. 1).
The two steps of the synthetic pathway are based on condensation
reactions giving only water as by-product. For these two steps,
green solvents, such as ethanol or ethyl lactate were used and the
purifications were done by precipitation and recrystallization.
chemistry allows the access to various p-conjugated structures that
can be tailored for the specific electronic or optical properties to
optimize the performances of the devices.9e12
Although current organic photovoltaic cell technology repre-
sents a promising clean energy production, it still falls short to
consider the green criteria for the conception of the organic
semiconductors. Indeed, the synthetic procedures of the
p-conju-
F
F
gated systems are essentially based on organometallic coupling
reaction, such as Stille or Kumada couplings for the syntheses of
oligo or polyheterocycles13e18 or the use of Wittig or Wittig Horner
reactions for building ethylenic bonds.15,19e22 Such synthetic
pathways involve stoichiometric amounts of by-products, which
require high degree of purification of the semiconducting materials.
Moreover, the resulting wastes are often toxic for the environment.
Nevertheless, possible alternatives consist in developing
F
F
R
O
F
O
N
N
O
F
O
R
Ia-c
F
F
Ia: R = H
F
F
Ib:
R = C5H11
R = CH2OC6H13
Ic:
* Corresponding author. Tel.: þ33 241735063; fax: þ33 24173546305; e-mail
ꢁ
address: pierre.frere@univ-angers.fr (P. Frere).
Fig. 1. Structure of the new conjugated derivatives Iaec.
0040-4020/$ e see front matter Ó 2012 Elsevier Ltd. All rights reserved.
http://dx.doi.org/10.1016/j.tet.2012.07.079

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C. Moussallem et al. / Tetrahedron 68 (2012) 8617e8621
Benzodifuran derivatives have been reported as hole trans-
3. X-ray structure of Ib
porting materials in organic electroluminescent cells28 or as
electron-donor in organic solar cells29,30 and several examples of
conjugated materials based on azomethine have been
described.31e34 Moreover furaldehyde and furyl alcohol used as
starting materials are well known as renewable materials that are
obtained by the dehydration of glucose or by transformation of
lignocellulosic biomass.35e37 Organic semiconductors based on
furan moieties have recently been evidenced in OFET and photo-
voltaic cells.38e40
The crystallographic structure of single crystal of Ib obtained by
slow evaporation of a chlorobenzene solution has been analyzed by
X-ray diffraction. The compound Ib crystallizes in the monoclinic
P21/c space group. As shown in Fig. 2, the two azomethine bonds are
coplanar with the central benzodifuran moiety and adopt an E
configuration. The two lateral perfluorophenyl groups are not co-
planar with the conjugated systems assuming a torsional angle of
55ꢀ with respect to the benzodifuran plane. The stacking of the
molecules present an overlapping of the perfluorophenyl moieties
with azomethine bonds and terminal furan units.46 The distances
between the planes of perfluorophenyl and furan cycles are close at
2. Synthesis
ꢂ
3.2 A. On the other hand, molecules are also in contact through
CeH/F interactions involving the hydrogen atoms of central ben-
The synthetic pathway of compounds Iaec is shown in Scheme 1.
The first step involves a Michael addition between the carbanion of
2-perfluorophenylacetonitrile 1 and the benzoquinone 2 that affords
after two intramolecular cyclisations the diaminobenzodifuran de-
rivative 3 in 40% yield.41e43 By using ethanol as solvent, the com-
pound 3 rapidly precipitates in the mixture. It is easily isolated by
filtration then washed with EtOH before using it for the next step
with no more purification. The conjugated system has been ex-
tended by the condensation of the two amino groups of 3 with an
excess of aldehyde derivatives 4aec (3 equiv). The condensation
reactions are carried out in the presence of a little amount of
P2O5 (10% mol) in ethyl lactate as solvent. Ethyl lactate can be con-
sidered as a green solvent miscible in water.44,45 Addition of meth-
anolewater (50/50 vol) mixture provokes the precipitation of
compounds Iaec that are obtained in 70e80% yields after filtration
and washing with methanol. Excess aldehyde can be partially re-
covered from the solution.
ꢂ
zene ring with dHeF distances of 2.61 A and the ones of terminal
ꢂ
furans with dHeF distances of 2.50 A (Fig. S1 in Supplementary data).
Fig. 2. X-ray structure of compounds Ib.
F
F
4. Theoretical calculations
O
F
F
F
F
F
NH3, H2O
EtOH
CN
+
In order to know the respective role of the pentafluorophenyl
and iminoefuran groups on the electronic properties of com-
pounds Iaec, theoretical calculations were performed at the ab
initio density functional level with the Gaussian09 package by
considering Iaec in a phase gas. Becke’s three parameters gradient-
corrected functional (B3LYP) with a polarized 6-31G (d,p) was used
for the geometrical optimization and for the HOMO and LUMO
levels determination. In order to limit the computational calcula-
tion time, pentyl or hexyl lateral chains of Ib and Ib were replaced
by methyl group. The theoretical data are gathered in Table 1 and
the contours of the orbitals for the HOMO and LUMO levels of Ib are
presented in Fig. 3. The optimized structures of Iaec present a good
planarity of the conjugated systems while the lateral penta-
fluorophenyls units present a torsional angle of 49ꢀ with benzo-
difuran moiety. The torsion angle between the benzodifuran
moiety and the perfluorophenyl groups are in agreement with the
X-ray structure of Ib. It can be noted that the use of the geometry
obtained from the X-ray structure to calculate the HOMO and
LUMO energy levels for Ib led to difference inferior at 5%. The
HOMO and the LUMO of compounds Iaec reside wholly at the
conjugated backbones (Fig. 3). By comparison with compound 3
F
O
F
H2N
NH2
F
O
1
F
2
O
F
3
F
F
F
Ethyl lactate
Ia-c
3
+
R
CHO
O
P2O5 (10% mol.)
4a-c
Scheme 1. Synthetic pathway of Iaec.
In order to increase the low solubility of the unsubstituted de-
rivative Ia, pentyl or hexyloxymethyl chains have been introduced by
using the aldehyde derivatives 4bec, obtained, respectively in 85
and 70% yields by the sequence BuLi/DMF from 5bec (Scheme 2).
The furan derivative 5b is available while 5c has been prepared in
75% yield by reaction of furyl alcohol with bromohexane in Aliquat
336 in the presence of KOH under microwave irradiation (t¼30 mn,
T¼80 ꢀC, P¼150 W).
Aliquat 336, KOH
HO
R
+
C6H13O
C6H13-Br
Table 1
O
microwave
O
5c
Calculated HOMO and LUMO levels and theoretical bandgapa
Compounds
HOMO (eV)
LUMO (eV)
DETh (eV)
BuLi, DMF
Et2O
3
ꢁ4.91
ꢁ5.07
ꢁ5.05
ꢁ5.06
ꢁ0.91
ꢁ2.36
ꢁ2.38
ꢁ2.37
4.0
b: R = C5H11
c: R= CH2OC6H13
Ia
Ib
Ic
2.71
2.67
2.68
O
R
CHO
O
4b-c
5b-c
a
Scheme 2. Syntheses of aldehydes 4bec.
B3LYP/6-31G(d,p).

C. Moussallem et al. / Tetrahedron 68 (2012) 8617e8621
8619
Fig. 3. Frontiers orbitals of compound Ib.
that presents a HOMO level at ꢁ4.91 eV, the replacement of the two
amino groups by the electron withdrawing azomethine junctions
leads to a slight stabilization of the HOMO for compounds Iaec at
ꢁ5.0 eV. By contrast the LUMO levels of Iaec are strongly stabilized
from ꢁ0.91 eV for 3 to ꢁ2.37 eV for Iaec, thus leading to a re-
duction of the bandgap to reach z2.7 eV for Iaec.
5. Electronic properties
The electronic properties of compounds 3 and Iaec have been
analyzed by cyclic voltammetry (CV) and by UVevis spectroscopy.
Electrochemical and optical data are gathered in Table 2.
Table 2
Electrochemical and optical data
Eoxa (V)
Ereda (V)
D
Eele (eV)
lmax (nm)
D
Eopd (eV)
b
c
Compounds
3
0.68, 0.82
1.22
1.18
d
d
318
452
469
461
3.9
2.6
2.4
2.5
Ia
Ib
Ic
ꢁ1.51
ꢁ1.51
ꢁ1.51
2.5
2.5
2.6
1.20
a
10ꢁ4 M in 0.1 M Bu4NPF6/CH2Cl2, scan rate 100 mV sꢁ1
.
b
c
Electrochemical bandgap
D
Eele¼EoxonsetꢁEredonset
.
10ꢁ4 M in CH2Cl2.
Fig. 4. CV trace of compound Ib 5$10ꢁ4 mol Lꢁ1 in 0.1 Bu4NPF6/CH2Cl2, top
d
Optical bandgap calculated from the onset of the absorption band.
v¼100 mV sꢁ1; bottom v¼200 mV sꢁ1 and v¼500 mV sꢁ1
.
The CV of 3 presents two reversible mono-electronic oxidation
waves at Eox1¼0.68 V and Eox2¼0.82 V corresponding to the suc-
cessive formation of a cation radical and a dication. By contrast for
compounds Iaec only one oxidation process is observed at around
1.2 V. As shown in Fig. 4 for Ib, by increasing the scan rate in po-
tential, the oxidation peak becomes reversible from a scan rate of
500 mV sꢁ1. For the reversible oxidation process at 500 mV sꢁ1 the
anodicecathodic peak separation is slightly inferior to 90 mV thus
suggesting a mono electronic process leading to the formation
a cation radical. Although no reduction process is observed for 3,
compounds Iaec present an irreversible reduction peak at
Ered¼ꢁ1.51 V. The more anodic oxidation for compounds Iaec
compared to 3 and the access to the reduction state agree with the
theoretical calculation that indicated the stabilization both of the
HOMO and LUMO levels for Iaec. Using an offset of ꢁ4.99 eV for
SCE versus the vacuum level and using the onset of the oxidation or
reduction peaks leads to estimate HOMO and LUMO levels about
ꢁ6.0 eV and ꢁ3.6 eV for compounds Iaec.47 The experimental data
are lower than the computational data (Table 2) but it should be
underlined that solvent effect was neglected in calculation. Nev-
ertheless the gap between HOMO and LUMO levels calculated from
computational or experimental data are very close with an elec-
Fig. 5. Normalized absorption spectra of 3 and Ib in solution in CH2Cl2 and film of Ib
deposited on glass.
trochemical bandgap measured at
DEelec¼2.5 eV.
Fig. 5 displays the UVevis absorption spectra of compounds 3 and
Ib in solution in CH2Cl2 and film of Ib on glass. Compound 3 presents
two absorption bands at 292 and 318 nm while compounds Iaec
show a structured absorption band around 500 nm with the for-
mation of three maxima. Vibronic fine structure in the absorption
band is the indication of a high degree of rigidification of the con-
jugated chain due to the combination of the intrinsically rigid ben-
zodifurane and the azomethine junctions. The lengthening of the
conjugated systems leads to a strong batchromic shift corresponding

8620
C. Moussallem et al. / Tetrahedron 68 (2012) 8617e8621
to a decrease of the HOMOeLUMO gap from 3.9 eV for 3 to 2.5 eV for
compounds Iaec. Films of Ib have been deposited on glass by spin
coating technique using chloroform as solvent. The UVevis absorp-
tion spectrum of the film shows a broader and structured absorption
band with the presence of three maxima at 512, 475 and 446 nm and
a shoulder at 410 nm. The film has been annealed till 130 ꢀC without
any UV spectrum modification indicating a good stability of the film.
For higher temperature, the intensity of the absorption decreases
due to a degradation of the film.
IR: 3110, 1481 cmꢁ1. Mass (MALDI-TOF):C22H6F10N2O2, Calcd
520.03 (Mþ), Found 519.4.
Anal. Calcd for C22H6F10N2O2: C, 50.70; H,1.15; N, 5.38. Found: C,
50.59; H, 1.40; N, 5.33.
7.2.2. 2-((Hexyloxy)methyl)furan: 5c. Furyl alcohol (0.156 mol,
13 mL), bromohexane (0.197 mol, 27.8 mL), KOH (0.23 mol, 12.9 g)
and aliquat 336 (7 mL) were stirred in a flask adapted for micro-
wave in open vessel. The mixture was irradiated under microwave
till the temperature reached 80 ꢀC and this temperature was
maintained for 30 min. Water was added to the mixture and the
aqueous phase was extracted with diethyl ether. The combined
organic phases were dried over MgSO4 and evaporated under
vacuum. The crude mixture was purified by distillation with
a Kugelroch apparatus under reduced pressure (P¼35 mbar,
Toven¼105 ꢀC) to afford 5c as a colourless oil in 75% yield.
6. Conclusion
In conclusion, we synthesized a new series of
p-conjugated
materials by following a green approach consisting in two sub-
sequent condensation reactions, which give only water as by-
products. The optical and electrochemical studies have shown
that the combination of the benzodifuran and furan units via azo-
methine junction leads to extended systems presenting electronic
properties adapted for applications in organic electronics. On the
other hand, the solubility of these compounds in common solvent
is beneficial for developing devices via solution processable tech-
niques, thus suggesting the interest of these compounds as semi-
conductors materials. The preparation of photovoltaic cells with
these materials, as well as analogues with longer conjugated chain,
is now underway and will be reported in future publications.
1H NMR (CDCl3): 7.40 (dd,1H, J¼1.8 Hz and J¼0.9 Hz), 6.32 (m, 2H),
4.34 (s, 2H), 3.45 (t, 2H, J¼6.6 Hz), 1.58 (q, 2H, J¼7.5 Hz),1.33 (m, 6H),
0.85 (t, 3H, J¼6.9 Hz) ppm 13C NMR (CDCl3): 152.1, 142.5, 110.1, 108.9,
70.3, 64.6, 31.7, 29.6, 25.8, 22.6, 13.9 ppm. MS (EI): m/z¼182 (100%).
7.3. General procedure for the formation of aldehydes 4b and
4c
To a stirred solution of compounds 5b or 5c (0.04 mol) in dry
ethyl ether (80 mL) at ꢁ10 ꢀC, was added dropwise n-BuLi
(1.2 equiv). The mixture was stirred for 30 min at ꢁ10 ꢀC and
quenched with DMF (2.2 equiv, 3.2 mL). The mixture was allowed to
warm to ambient temperature and was stirred for 4 h. An ammo-
nium chloride solution (20 mL, 1 M) was added. The aqueous phase
was then extracted with ethyl acetate. The combined organic layers
were dried over MgSO4, filtrated, concentrated in vacuum and
purified by column chromatography.
7. Experimental section
7.1. General
NMR spectra were recorded on a Bruker Avance 300 (1H and 19F:
300.1 MHz, 13C: 75.7 MHz, T¼300 K). The spectra were referenced
against the internal NMR-solvent standard. Chemical shifts were
expressed in parts per million (ppm) and were reported as s (sin-
glet), d (doublet), t (triplet), td (doublet triplet), m (multiplet) and
coupling constants J were given in Hz. Mass spectra were recorded
under EI mode on a VG-Autospec mass spectrometer or under
MALDI-TOF mode on a MALDI-TOF-MS BIFLEX III Bruker Daltonics
spectrometer. The main peaks are described according to m/z. The
7.3.1. 5-Pentylfuran-2-carbaldehyde 4b. Eluent for the chromatog-
raphy: ethyl acetateecyclohexane (2e8).
Pale yellow oil, 5.81 g, 85% yield.
1H NMR (CDCl3): 9.51 (s, 1H), 7.16 (d, 1H, J¼3.3 Hz), 6.22 (d, 1H,
J¼3.3 Hz), 2.71 (t, 2H, J¼7.5 Hz),1.69 (m, 2H),1.33 (m, 4H), 0.89 (t, 3H,
J¼6.9 Hz) ppm 13C NMR (CDCl3): 177.1, 164.3, 151.7, 123.9 (broad sig-
nal), 108.7, 31.3, 28.4, 27.2, 22.3, 13.9 ppm. MS (EI): m/z¼166 (100%).
ꢂ
peak corresponding to molecular mass is expressed as (Mþ ). IR
Spectra were performed on a Bruker VERETEX 70. UV-visible op-
tical data were recorded with a PerkineElmer lambda 19 spectro-
photometer. HPLC solvents were used for the measurements.
Electrochemical experiments were performed with a Biologic
SP150 potentiostat in a standard three electrodes cell using plati-
num electrodes and a saturated calomel reference electrode (SCE).
1,4-benzoquinone 1, pentafluorophenylacetonitrile 2, 2-furyl
alcohol, 2-furaldehyde 4a and 2-pentylfuran 4b were purchased
from Acros or Lancaster and used without further purification.
7.3.2. 5-((Hexyloxy)methyl)furan-2-carbaldehyde 4c. Eluent for the
chromatography: ethyl acetateecyclohexane (3e7).
Pale yellow oil, 6.3 g, 70% yield.
1H NMR (CDCl3): 9.52 (s, 1H), 7.14 (d, 1H, J¼3.3 Hz), 6.44 (d, 1H,
J¼3.3 Hz), 4.44 (s, 2H), 3.43 (t, 2H, J¼6.6 Hz), 1.51 (q, 2H, J¼7.8 Hz),
1.25 (m, 6H), 0.80 (t, 3H, J¼6.9 Hz) ppm 13C NMR (CDCl3): 177.8,
158.9, 152.5, 122.2 (broad signal), 111.0, 71.4, 64.9, 31.6, 29.5, 25.7,
22.5, 14.0 ppm. MS(EI): m/z¼210 (100%).
7.2. Preparation of precursors 3 and 5c
7.4. General procedure for the formation of Iaec
7.2.1. 3,7-Bis(perfluorophenyl)benzo[1,2-b:4,5-b0]difuran-2,6-
diamine: 3. 2,3,4,5,6-Pentafluorophenylacetonitrile
2
(7.1 ml,
Aldehyde 4aec (3 equiv, 0.57 mmol) and a catalytic amount of
P2O5 were successively added to a solution of 3 (100 mg, 0.19 mmol)
in ethyl lactate (3 mL) at room temperature. After one night stirring,
the solution was poured in 10 ml of wateremethanol. (50/50 vol)
solution to give a precipitate. After filtration, the solid was re-
covered, washed with methanol (30 mL) and dried under vacuum.
3 equiv, 55.5 mmol) was added to a solution of 1,4-benzoquinone 1
(2.0 g, 18.5 mmol) in ethanol (50 mL) at room temperature. Then
addition of an excess of aqueous solution of ammoniac (7.0 mL)
resulted in a fast exothermic reaction and precipitation of a white
solid. After 1 h stirring the solid was recovered by filtration and was
washed with ethanol (25 mL). Drying under vacuum afforded 3.8 g
(40%) of 3 as a white powder, which was used in the next step
without any further purification.
7.4.1. 2,6-N-Di[(furan-20-yl)carboxylimino]-benzo[1,2-b:4,5-b0]di-
furan-3,7 pentafluorophenyl: Ia. Orange solid; yield 60%. The solu-
bility is too low for allowing purification by chromatography or
recrystallization.
Mp: 260 ꢀC. 1H NMR (DMSO-d6): 6.98 (s, 2H), 6.68 (s, 4H) ppm
19F NMR (DMSO-d6): ꢁ139.7 (dd, 4F, J¼6.8 Hz, J¼22.4 Hz), ꢁ162.3 (t,
2F, J¼22.4 Hz), ꢁ165.8 (td, 4F, J¼6.8 Hz, J¼22.4 Hz) ppm 13C NMR
(DMF-d7): 157.9, 146.9, 124.2, 108.7, 97.6, 75.5 ppm.
1H NMR (CDCl3) saturation: 8.77 (s, 1H), 7.70 (d, 1H, J¼3.3 Hz),
7.43 (s, 1H), 7.14 (d, 1H, J¼3.3 Hz), 6.63 (m, 1H) ppm.

C. Moussallem et al. / Tetrahedron 68 (2012) 8617e8621
8621
IR: 3115, 1487 cmꢁ1. Mass (MALDI-TOF): C32H10F10N2O4, Calcd
version, at http://dx.doi.org/10.1016/j.tet.2012.07.079. These data
include MOL files and InChiKeys of the most important compounds
described in this article.
677.0 (MþþH), Found 676.6.
7.4.2. 2,6-N-Di[(50-pentylfuran-20-yl)carboxylimino]-benzo[1,2-
b:4,5-b0]difuran-3,7-pentafluoro-phenyl: Ib. Recrystallisation from
ethyl acetate solution, orange solid; yield 58%; Mp: 212 ꢀC.
1H NMR (CDCl3): 8.64 (s, 2H), 7.35 (s, 2H), 7.03 (d, 2H, J¼3.6 Hz),
6.22 (d, 2H, J¼3.6 Hz), 2.73 (t, 4H, J¼7.5 Hz), 1.70 (q, 4H, J¼7.2 Hz),
1.36 (m, 8H), 0.91 (t, 6H, J¼7.0 Hz) ppm 19F NMR (CDCl3): ꢁ139.46
(dd, 4F, J¼6.8 Hz, J¼22.4 Hz), ꢁ157.22 (t, 2F, J¼22.4 Hz), ꢁ164.79 (td,
4F, J¼6.8 Hz, J¼22.4 Hz) ppm 13C NMR (CDCl3): 163.4, 155.4, 150.8,
149.0, 145.7, 134.8, 127.3, 121.1, 109.2, 101.2, 31.4, 28.5, 27.3, 22.4,
13.9 ppm.
References and notes
1. Pron, A.; Gawrys, P.; Zagorska, M.; Djurado, D.; Demadrille, R. Chem. Soc. Rev.
2010, 39, 2577e2632.
2. Klauk, H. Chem. Soc. Rev. 2010, 39, 2643e2666.
3. Cheng, Y.-J.; Yang, S.-H.; Hsu, C.-S. Chem. Rev. 2009, 109, 5868e5923.
€
4. Mishra, A.; Bauerle, P. Angew. Chem., Int. Ed. 2012, 51, 2020e2067.
5. Arias, A. C.; MacKenzie, J. D.; McCulloch, I.; Rivnay, J.; Salleo, A. Chem. Rev. 2010,
110, 3e24.
6. Mas-Torrent, M.; Rovira, C. Chem. Soc. Rev. 2008, 37, 827e838.
7. Walker, B.; Kim, C.; Nguyen, T.-Q. Chem. Mater. 2011, 23, 470e482.
8. Leong, W. L.; Mathews, N.; Tan, B.; Vaidyanathan, S.; Dotz, F.; Mhaisalkar, S. J.
Mater. Chem. 2011, 21, 5203e5214.
IR: 3120, 1491 cmꢁ1. Mass (MALDI-TOF): C42H30F10N2O4, Calcd
817.20 (MþþH), Found 816.8. Anal. Calcd for C42H30F10N2O4: C,
61.77; H, 3.70; N, 3.43. Found: C, 61.81; H, 3.64; N, 3.75.
9. Roncali, J. Acc. Chem. Res. 2009, 42, 1719e1730.
10. Mishra, A.; Ma, C.-Q.; Bauerle, P. Chem. Rev. 2009, 109, 1141e1276.
11. Roncali, J. Macromol. Rapid Commun. 2007, 28, 1761e1775.
12. Kanibolotsky, A. L.; Perepichka, I. F.; Skabara, P. J. Chem. Soc. Rev. 2010, 39,
2695e2728.
7.4.3. 2,6-N-Di[(50(2-2-oxa-heptylfuran-20-yl))carboxylimino]-benzo
[1,2-b:4,5-b0]difuran-3,7-pentafluoro-phenyl:
Ic. Recrystallisation
13. Carsten, B.; He, F.; Son, H. J.; Xu, T.; Yu, L. Chem. Rev. 2011, 111, 1493e1528.
14. Zhou, H.; Yang, L.; Stuart, A. C.; Price, S. C.; Liu, S.; You, W. Angew. Chem., Int. Ed.
2011, 50, 2995e2998.
from ethyl acetate solution, orange solid; yield 65%; Mp: 210 ꢀC.
1H NMR (CDCl3): 8.70 (s, 2H), 7.37 (s, 2H), 7.07 (d, 2H, J¼3.3 Hz),
6.51 (d, 2H, J¼3.6 Hz), 4.54 (s, 4H), 3.52 (t, 4H, J¼6.6 Hz), 1.60 (m,
4H), 1.29 (m, 12H), 0.88 (t, 6H, J¼6.9 Hz) ppm 19F NMR (CDCl3):
ꢁ139.53 (dd, 4F, J¼6.8 Hz, J¼22.4 Hz), ꢁ158.82 (t, 2F, J¼22.4 Hz),
ꢁ164.55 (td, 4F, J¼6.8 Hz, J¼22.4 Hz) ppm 13C NMR (CDCl3): 158.0,
155.1, 152.1, 149.1, 146.0, 127.4, 111.7, 109.9, 101.4, 71.2, 65.1, 31.7,
29.6, 25.8, 22.6, 14.0 ppm. IR: 3121, 1492 cmꢁ1. Mass (MALDI-TOF):
C46H38F10N2O6, Calcd 905.3 (MþþH), Found 905.7. Anal. Calcd for
C46H38F10N2O6: C, 61.06; H, 4.23; N, 3.10. Found: C, 60.68; H, 4.21; N,
3.18.
ꢁ
15. Turbiez, M.; Frere, P.; Allain, M.; Videlot, C.; Ackermann, J.; Roncali, J. Chem.
dEur. J. 2005, 11, 3742e3752.
16. Hassan, J.; Sevignon, M.; Gozzi, C.; Schulz, E.; Lemaire, M. Chem. Rev. 2002, 102,
1359e1469.
17. Sheina, E.; Liu, J.; Iovu, M. C.; Laird, D. W.; McCullough, R. D. Macromolecules
2004, 37, 3526e3528.
18. Tkachov, R.; Senkovskyy, V.; Komber, H.; Kiriy, A. Macromolecules 2011, 44,
2006e2015.
19. Segura, J. L.; Martin, N.; Hanack, M. Eur. J. Org. Chem. 1999, 643e651.
ꢁ
20. Jestin, I.; Frere, P.; Mercier, N.; Levillain, E.; Stievenard, D.; Roncali, J. J. Am.
Chem. Soc. 1998, 120, 8150e8158.
ꢁ
21. Frere, P.; Raimundo, J. M.; Blanchard, P.; Delaunay, J.; Richomme, P.; Sauvajol, J.
L.; Orduna, J.; Garin, J.; Roncali, J. J. Org. Chem. 2003, 68, 7264e7265.
ꢁ
22. Turbiez, M.; Frere, P.; Roncali, J. Tetrahedron 2005, 61, 3045e3053.
7.5. X-ray structure of Ib
ꢁ
23. Ho, H. A.; Brisset, H.; Elandaloussi, E. H.; Frere, P.; Roncali, J. Adv. Mater. 1996, 8,
990e994.
X-ray single-crystal diffraction data were collected at 293 K on
a BRUKER KappaCCD diffractometer, equipped with a graphite
24. Egbe, D. A. M.; Neugebauer, H.; Sariciftci, N. S. J. Mater. Chem. 2011, 21,
1338e1349.
25. Mealares, C.; Gandini, A. Polym. Int. 1996, 40, 33e39.
ꢀ
ꢂ
monochromator utilizing MoK
a
radiation
(l
¼0.71073A). The
26. Guarin, S. A. P.; Bourgeaux, M.; Dufresne, S.; Skene, W. G. J. Org. Chem. 2007, 72,
structure was solved by direct methods and refined on F2 by full
matrix least-squares techniques using SHELX97 package (G.M.
Sheldrick, 1998). All non-hydrogen atoms were refined anisotrop-
ically and the H atoms were added by calculation and treated with
a riding model. Absorption was corrected by SADABS program
(Sheldrick, Bruker, 2008).
2631e2643.
27. Barik, S.; Skene, W. G. Macromolecules 2010, 43, 10435e10441.
28. Tsuji, H.; Mitsui, C.; Sato, Y.; Nakamura, E. Adv. Mater. 2009, 21, 3776e3779.
29. Li, H.; Jiang, P.; Yi, C.; Li, C.; Liu, S.-X.; Tan, S.; Zhao, B.; Braun, J.; Meier, W.;
Wandlowski, T.; Decurtins, S. Macromolecules 2010, 43, 8058e8062.
30. Huo, L.; Huang, Y.; Fan, B.; Guo, X.; Jing, Y.; Zhang, M.; Li, Y.; Hou, J. Chem.
Commun. 2012, 3318e3320.
31. Tshibaka, T.; Bishop, S.; Roche, I. U.; Dufresne, S.; Lubell, W. D.; Skene, W. G.
Chem.dEur. J. 2011, 17, 10879e10888.
7.5.1. Crystal data for Ib. Red plate (0.46ꢃ0.39ꢃ0.05 mm3),
C42H30F10N2O4, Mr¼816.78, monoclinic, space group P21/c,
32. Dufresne, S.; Bolduc, A.; Skene, W. G. J. Mater. Chem. 2010, 20, 4861e4866.
33. Sek, D.; Iwan, A.; Jarzabek, B.; Kaczmarczyk, B.; Kasperczyk, J.; Mazurak, Z.;
Domanski, M.; Karon, K.; Lapkowski, M. Macromolecules 2008, 41, 6653e6663.
34. Barik, S.; Bletzacker, T.; Skene, W. G. Macromolecules 2012, 45, 1165e1173.
35. Chheda, J. N.; Huber, G. W.; Dumesic, J. A. Angew. Chem., Int. Ed. 2007, 46,
7164e7183.
36. Binder, J. B.; Raines, R. T. J. Am. Chem. Soc. 2009, 131, 1979e1985.
37. Hu, S.; Zhang, Z.; Zhou, Y.; Han, B.; Fan, H.; Li, W.; Song, J.; Xie, Y. Green. Chem.
2008, 10, 1280e1283.
38. Gidron, O.; Dadvand, A.; Sheynin, Y.; Bendikov, M.; Perepichka, D. F. Chem.
Commun. 2011, 1976e1978.
39. Woo, C. H.; Beaujuge, P. M.; Holcombe, T. W.; Lee, O. P.; Frechet, J. M. J. J. Am.
Chem. Soc. 2010, 132, 15547e15549.
40. Bijleveld, J. C.; Karsten, B. P.; Mathijssen, S. G. J.; Wienk, M. M.; de Leeuw, D. M.;
Janssen, R. A. J. J. Mater. Chem. 2011, 21, 1600e1606.
41. Obushak, M. D.; Martyak, R. L.; Matiychuk, V. S. Pol. J. Chem. 2002, 76,
1419e1424.
¼108.048(4)ꢀ,
ꢂ
ꢂ
ꢂ
a¼15.6792(8) A, b¼12.1688(7) A, c¼10.5804(6) A,
b
3
V¼1918.4(2) A , Z¼2, rcalcd¼1.413 gcmꢁ3
,
m
(MoKa)¼0.124 mmꢁ1
,
ꢂ
F(000)¼836, qmin¼4.05ꢀ, qmax¼27.54ꢀ, 36,101 reflections collected,
4364
unique
(Rint¼0.1247),
restraints/parameters¼0/263,
R1¼0.0675 and wR2¼0.1334 using 2144 reflections with I>2
R1¼0.1656 and wR2¼0.1730 using all data, GOF¼1.037,
ꢂꢁ3
s(I),
ꢁ0.335<Dr<0.383e A
.
ꢀ
Crystallographic data excluding structure factors have been
deposited with the Cambridge Crystallographic Data under refer-
ence CCDC: 858095.
42. Caruso, H.; Panunzi, B.; Roviello, G. N.; Roviello, G.; Tingoli, M.; Tuzi, A. C. R.
Acknowledgements
Chim. 2009, 12, 622e634.
43. (a) Yi, C.; Blum, C.; Lehmann, M.; Keller, S.; Liu, S.-X.; Frei, G.; Neels, A.; Hauser,
ꢀ
We thank Angers Loire Metropole for the fellowship accorded
€
J.; Schurch, S.; Decurtins, S. J. Org. Chem. 2010, 75, 3350e3357; (b) Keller, S.; Yi,
C.; Li, C.; Liu, S.-X.; Blum, C.; Frei, G.; Sereda, O.; Neels, A.; Wandloswki, T.;
Decurtins, S. Org. Biomol. Chem. 2011, 9, 6410e6416.
for the PhD of C.M.
44. Pereira, C. S. M.; Silva, V. M. T. M.; Rodrigues, A. E. Green. Chem. 2011, 13,
2658e2671.
Supplementary data
45. Bennett, J. S.; Charles, K. L.; Miner, M. R.; Heuberger, C. F.; Spina, E. J.; Bartels,
M. F.; Foreman, T. Green. Chem. 2009, 11, 166e168.
46. Mallet, C.; Allain, M.; Leriche, P.; Frere, P. CrystEngComm 2011, 13, 5833e5840.
47. Cardona, C. M.; Li, W.; Kaifer, A. E.; Stockdale, D.; Bazan, G. C. Adv. Mater. 2011,
23, 2367e2371.
Copies of 1H and 13C and 19F NMR of compounds 3, 4b, 4c, 5c, Ib
and Ic. Fig. S1 presenting the packing of Ib in the crystal. Supple-
mentary data associated with this article can be found, in the online
ꢁ