Novel aspects of a convenient synthesis and of electroproperties of derivatives based on diphenylamine

Article abstract of DOI:10.1002/hlca.200890065

The substituted monomers 4a,c,d, 5a,b, 6a, 7a,b, and 8a of novel poly(diphenylamines), possessing the respective photochromic groups, were synthesized by the Stille cross-coupling methodology (Scheme). The hyperbranched structures were characterized by ¹H- and ¹³C-NMR spectroscopy. The obtained monomers show good stability in common organic solvents such as CHCl₃, toluene, and CH₂Cl₂, and exhibit excellent thermal stability. Electrochemical results and theoretical calculations suggest that oxidation and reduction of the monomers start from the side of the amine function and the five-membered heterocyclic ring moieties, respectively.

Full text of DOI:10.1002/hlca.200890065

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Novel Aspects of a Convenient Synthesis and of Electroproperties of
Derivatives Based on Diphenylamine
by Krzysztof Idzika), Jadwiga Sołoducho*a), Joanna Cabaja), Mariusz Mosia˛dza), Mieczysław
Łapkowskib), and Sylwia Golbab)
a
´
) Wrocław University of Technology, Department of Chemistry, Wybrzez˙e Wyspianskiego 27,
PL-50-370 Wrocław
b) Silesian University of Technology, Department of Chemistry, Strzody 9, PL-44-100 Gliwice
The substituted monomers 4a,c,d, 5a,b, 6a, 7a,b, and 8a of novel poly(diphenylamines), possessing
the respective photochromic groups, were synthesized by the Stille cross-coupling methodology
1
(Scheme). The hyperbranched structures were characterized by H- and 13C-NMR spectroscopy. The
obtained monomers show good stability in common organic solvents such as CHCl3, toluene, and
CH2Cl2, and exhibit excellent thermal stability. Electrochemical results and theoretical calculations
suggest that oxidation and reduction of the monomers start from the side of the amine function and the
five-membered heterocyclic ring moieties, respectively.
1. Introduction. – Advances in organic electronics have triggered intensive research
effort towards the development of efficient materials owing excellent performance and
potential applications [1].
Polymers constructed from diphenylamine (DPA) building blocks [2] are versatile
materials that exhibit a variety of advanced functional properties such as high hole-
transporting and light-emitting efficiencies, large two-photon absorption cross sections,
high photorefractivity and photoconductivity, and large stabilization effect on high-spin
polyradicals in organic magnets. These materials thus promise an array of technological
applications in organic electronics, photonics, and spintronics. The multifaceted
functionalities of such materials are partially associated with good co-planarity of the
aromatic rings surrounding the central N-atom in the phenylamine unit. The lone-pair
electrons on the central N-atom help to enhance the electronic communication along
the macromolecular chains and make them to behave as strong electron donors.
Many research groups have worked on the design and synthesis of DPA-based
linear polymers. The frontier of polymer research is now moving from the macro-
molecules with a one-dimensional linear structure to three-dimensional dendritic/
hyperbranched structures, with the expectation that the novel molecular architecture of
the latter will impact functional properties that are inaccessible by the former [3].
2. Results and Discussion. – 2.1. Synthesis. Supplementing our previous publication
[4], we now report a systematic investigation on the synthesis and electrochemical and
field effects of carriers in a series of new polymer semiconductors based on
diphenylamine. The new conjugated monomers 4 – 8 were obtained from commercially
available diphenylamine 1 by a multi-step procedure according to the synthetic route
ꢀ 2008 Verlag Helvetica Chimica Acta AG, Zürich

Helvetica Chimica Acta – Vol. 91 (2008)
619
Scheme
shown in the Scheme. Bromination of 1 at the 4-positions was achieved by potas-
sium bromide/potassium bromate in AcOH, which gave bis(4-bromophenyl)amine
(2). The amino group in 2 was alkylated by RBr in the presence of benzyltriethyl-
ammonium chloride ((BnEt3N)Cl) as phase-transfer catalyst to yield the tertiary
amines 3a – d. Palladium-catalyzed Stille coupling [4] of the amines 3 with tributyl(2-
thienyl)-, tributyl(furan-2-yl)-, tributyl(pyridin-2-yl)-, tributyl(2,3-dihydrothieno[3,4-
b]-1,4-dioxin-5-yl)-, and tributyl(oxazol-2-yl)stannane in toluene gave bis(4-aryl-
phenyl)amine monomers 4a,c,d, 5a,b, 6a, 7a,b, and 8a. All the monomers were
obtained as colorful oils or solids and characterized by spectroscopic methods, from
which satisfactory spectral data corresponding to their molecular structures were obtained.
2.2. Properties of Langmuir– Blodgett (LB) Films Built from Diphenylamine
Derivatives. Building on our previous experience in the field of surface chemistry, we
conducted LB experiments. For instance, an N-alkylbis[4-(2-thienyl)phenyl]amine 4,
dissolved in an organic solvent (CHCl3), was spread on water. Then the organic layer
was deposited by the LB technique onto a set of eight interdigital, buried Au-electrodes
(200 mm wide and spaced) photolithographically fixed on a thermally coated silicon
(SiO2) substrate. Etching canals in the silicon substrate were then filled by a mixture of
gold and trace amounts of tungsten. This configuration provides flat, polished
(measured by the interferometric method) electrodes, ready for LB deposition. All
initially nonmeasured under-water films were deposited at a velocity lower than the
draining rate of film of carboxylic acids, i.e., 1.3 mm/min. After deposition, the films
were stored in a vacuum desiccator prior to use.
Langmuir monomolecular films of diphenylamine derivative 4c were spread from
the CHCl3 solution on high-purity H2O at 296 K. Langmuir – Blodgett deposition was
carried out with a KSV-5000-LB system at a surface pressure of ca. 20 – 25 mN/m2.

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The sample processing was carried out at ca. 296 K, whereas conductivity was
measured at 296, 333, and 358 K.
The transference of the obtained LB film was of the Y-type in the first deposition
and of the Z-type in the following ones. The relationship between absorbance and
number of layers and the constant transfer ratio during the deposition indicated a
constant architecture of the LB-film layers. The absorption spectra of the diphenyl-
amine-derivative-deposited films confirm also the formation of homogeneous films in
good yield (Fig. 1).
Fig. 2 shows typical I – V curves of fabricated LB films at room temperature. The I –
V curves are asymmetric and nonlinear. The forward currents follow approximately an
exponential trend. This I – V behavior is connected with diode-like-type conductivity.
Fig. 1. Absorption spectra of LB films obtained from N-nonylbis[4-(2-thienyl)phenyl]amine (4c)/
docosanoic acid 2 :1
Fig. 2. Current – voltage characteristics of a 20-layer LB film built from N-nonylbis[4-(2-thienyl)phenyl]-
~
&
^
amine (4c)/docosanoic acid 2 :1. ¼ First, ¼ second, ¼ third, and ¼ fourth cycle.

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621
From current – voltage characteristics obtained at higher temperatures (333 K,
358 K, Fig. 3), it was found that the characteristics of the I – V curves become quite
linear and symmetrical. The forward currents increased strongly with increasing
voltage. At higher temperatures, phenomena of improvement in conjugation of the
conducting system are observed. When transient intermolecular charge transfer occurs
in a more sustained manner, the character of conductivity is changed and remains
linear.
Fig. 3. Current – voltage characteristics of a 20-layer LB film built from N-nonylbis[4-(2-thienyl)phenyl]-
amine (4c)/docosanoic acid 2 :1 at different temperatures
Therefore, these results indicate that the obtained films behave as p-type
semiconductors. Moreover, good environmental stabilities were observed for the
material, what makes it a very promising candidate for sensing elements.
2.3. Electrochemical Effects of Diphenylamine Derivatives. Diphenylamine deriv-
atives are able to undergo an oxidative polymerization process according to an
established mechanism of electropolymerization [5][6]; the first redox system is
attributed to a single-electron oxidation to a radical cation, and the second one leads to
a dication (BTFA ¼ 4a).
BTFA ! BTFAþ þ eꢀ
BTFAþ ! BTFAþþ þ eꢀ
In the case of a series of methylated oligothiophenes, the first oxidation potential is
progressively shifted to more negative values with increasing size of the conjugated
backbone, and in addition the oxidation process becomes more and more reversible
[7]. In contrast, diphenylamine derivatives of thiophene exhibit reversible oxidation
processes, independently of the size of the backbone.
However, the synthesized monomer 4a is only partially soluble in organic solvents
(MeCN) due to its rigid backbone. By gel-permeation chromatography (GPC) against
polystyrene standards in THF, the mass-average molecular mass Mw of the polymer
pBTFA is determined to be 4900 (Mn ¼ 2080, polydispersity near 2.3). The low Mw of

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the pBTFA polymer is associated with its poor solubility in organic solvents, and only
the THF-soluble fraction was characterized.
The thermal properties of the polymer were evaluated by thermogravimetric
analysis (TGA). TGA revealed that the onset decomposition temperature of the
polymer under N2 was 3908.
BTFA (4a) is oxidized by a three-step process (Fig. 4), as revealed by three clear
oxidation peaks at 0.4, 0.9, and 1.4 V and three reduction peaks at the potentials 0.18,
0.18, and 0.33 V. All oxidation processes are reversible. When the oxidation process is
ranged to the first oxidation peak, the value of the reduction peak is placed at the
potential 0.18 V. In this case, the compound is not electropolymerized, but when the
potential increases included the second oxidation peak, we could observe the growing
of electroactive yellow layers on the electrode (Fig. 5). The polymer obtained from 4a
did not show a reduction wave in the range 0 to ꢀ 3.0 V which suggests that this
polymer is an intrinsic p-type semiconductor.
Fig. 4. Cyclic voltammetry of N-butylbis[4-(2-thienyl)phenyl]amine (¼ BTFA; 4a) in 0.3 mm solution of
0.1m (Bu4N)BF4 in MeCN. Potential sweep rate v ¼ 50 mV/s.
In the case of 5a (¼ BFFA), we observed a multistep oxidative process (Fig. 6). We
found two main, clear oxidation peaks at 0.3 and 1.1 Vand one reduction peak at 0.08 V.
The entire oxidative process is irreversible. The compound polymerizes near the
potential associated with the first oxidation peak, and gave a yellow electroactive film
(Fig. 7). Similarly to 4a, the obtained polymer is probably of low molecular mass Mw for
the reason given above.
Furthermore, future synthetic modifications will allow to produce unique soluble
hybrid polymers that display the same range of tenability. The application of such
copolymers to dynamic electrochromic devices, both large and small, will be an
important and compelling advancement in the field of electrochromic and conducting
heterocyclic polymers.

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Fig. 5. Cyclic voltammetry of a poly(BTFA) film in 0.1m solution of (Bu4N)BF4 in MeCN. Potential
sweep rate v ¼ 50 mV/s.
Fig. 6. Cyclic voltammetry of N-butylbis[4-(furan-2-yl)phenyl]amine (¼ BFFA; 5a) in 0.3 mm solution of
0.1m (Bu4N)BF4 in MeCN. Potential sweep rate v ¼ 50 mV/s.
2.4. Theoretical Study of the Geometry of Diphenylamine Derivatives. DPA
derivatives have an almost planar structure which determines the luminescence
characteristics. From our previous experience and theoretical calculations [8], we know
that the amine group is able to give a salt with a tetrahedric structure of the N-atom,
thus initiating the electropolymerization (see 2.3.).

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Fig. 7. Cyclic voltammetry of a poly(BFFA) film in 0.1m solution of (Bu4N)BF4 in MeCN. Potential
sweep rate v ¼ 50 mV/s.
In the calculated structure of a dimer moiety of 4a, we found blocked transient
intermolecular charge transfer (ICT) due to a blocked conjugation (Fig. 8). This
phenomenon is illustrated by the HOMO – LUMO visualization (Fig. 9). With
increasing temperature, continuous conjugation and better conductivity is possible.
Fig. 8. Calculated structure of a dimer moiety of N-butylbis[4-(2-thienyl)phenyl]amine (4a)
The theoretical study established clear structure – property relationships of the
DPA polymers, i.e., the desired electrochemical properties are correlated to the
decreasing number of monomer units in the polymer.
3. Conclusions. – In continuation of our previous studies [4][9][10], we performed
the efficient synthesis of the novel series of substituted diphenylamine derivatives 4 – 8,
and investigated their functional properties in view of their use as building blocks for
electrochemical processing and surface electrochemistry (LB films). Thus, Pd-
catalyzed Stille cross coupling yielded a series of thiophene, furan, pyridine,
thienodioxine, and oxazole derivatives 4 – 8 of DPA in 60 – 90% yield.

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Fig. 9. HOMO – LUMO visualization of N-butylbis[4-(2-thienyl)phenyl]amine (4a)
It should be pointed out that to achieve the improved functional properties of the
described materials, it is of great importance to incorporate the electron-donating
diphenylamine moiety as a central core in the monomer units. We believe that materials
obtained from DPA derivatives may lead to a further increase of the field-effect
mobility and thus make these materials attractive for applications in organic sensors,
electronic, spintronics, and electrochromic devices [11]. The current strategy is very
promising for the application of DPA derivatives as novel building blocks designed for
the production of p-type semiconductor materials.
Financial support from the Wrocław University of Technology, Grant No 332093, is gratefully
acknowledged. We would like to thank also the Wroclaw Center for Networking and Supercomputing
(WCSS) for generous allotment of computer time.
Experimental Part
1. General. Stille reactions were performed under N2. Solvents were carefully dried and distilled from
appropriate drying agents prior to use. Commercially available reagents were used without further
purification, unless otherwise stated. Monomers 3 were prepared by a standard method [2], and 4 – 8 by
the general experimental methodology described in our previous papers (see [4]). Bis(4-bromophenyl)-
amine (¼4-bromo-N-(4-bromophenyl)benzenamine; 2) was obtained according to a standard method
[5]. TLC: Merck pre-coated glass plates; visualization with UV light. Flash chromatography (FC): silica
gel from Merck (230 – 400 mesh). NMR Spectra: Bruker-300 spectrometer; CDCl3 solns.; chemical shifts
d rel. to internal SiMe4, J in Hz.
2. Monomers. 2.1. N-Alkylbis(4-bromophenyl)amines 3a – d. The amines 3a – d were synthesized
according to [2] by N-alkylation of 2 (3.27 g, 10.0 mmol) with RBr (12.0 mmol) in the presence of
(BnEt3N)Cl (1.0 g, 4.39 mmol) as phase-transfer catalyst in toluene/50% aq. NaOH soln.
N-Butylbis(4-bromophenyl)amine (¼4-Bromo-N-(4-bromophenyl)-N-butylbenzenamine; 3a):
1
White microcrystals (3.45 g, 90%). M.p. 61 – 628. H-NMR (CDCl3): 7.37 (d, J ¼ 8.9, 4 H); 6.88 (d, J ¼
8.9, 4 H); 3.65 (t, J ¼ 7.7, 2 H); 1.66 – 1.62 (m, 2 H); 1.41 – 1.30 (m, 2 H); 0.96 (t, J ¼ 7.3, 3 H).
13C-NMR: 146.7; 132.3; 122.6; 113.9; 52.2; 29.4; 20.3; 14.0. Anal. calc. for C16H17Br2N: C 50.16, H 4.47, N
3.66; found: C 50.46, H 4.40, N 3.71.

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N-Heptylbis(4-bromophenyl)amine (¼4-Bromo-N-(4-bromophenyl)-N-heptylbenzenamine; 3b):
1
White microcrystals (3.62 g, 85%). M.p. 45 – 468. H-NMR: 7.32 (d, J ¼ 8.9, 4 H); 6.82 (d, J ¼ 8.9, 4 H);
3.59 (t, J ¼ 7.7, 2 H); 1.61 – 1.53 (m, 2 H); 1.27 – 1.23 (m, 8 H); 0.86 (t, J ¼ 6.8, 3 H). 13C-NMR: 146.7;
132.2; 122.5; 113.8; 52.4; 31.8; 29.0; 27.2; 26.9; 22.6; 14.0. Anal. calc. for C19H23Br2N: C 53.67, H 5.45, N
3.29; found: C 53.77, H 5.49, N. 3.20.
N-Nonylbis(4-bromophenyl)amine (¼4-Bromo-N-(4-bromophenyl)-N-nonylbenzenamine; 3c):
1
Pinkmicrocrystals (3.72 g, 82%). M.p. 30 – 31 8. H-NMR: 7.36 (d, J ¼ 8.9, 4 H); 6.86 (d, J ¼ 8.9, 4 H);
3.63 (t, J ¼ 7.7, 2 H); 1.69 – 1.56 (m, 2 H); 1.39 – 1.21 (m, 12 H); 0.90 (t, J ¼ 6.7, 3 H). 13C-NMR: 146.7;
132.2; 122.5; 113.8; 52.4; 31.8; 29.5; 29.4; 29.2; 27.2; 27.0; 22.7; 14.1. Anal. calc. for C21H27Br2N: C 55.65, H
6.00, N 3.09; found: C 55.56, H 6.11, N 2.99.
N-Dodecylbis(4-bromophenyl)amine (¼4-Bromo-N-(4-bromophenyl)-N-dodecylbenzenamine; 3d):
Brown oil (3.96 g, 80%). 1H-NMR: 7.35 (d, J ¼ 8.9, 4 H); 6.86 (d, J ¼ 8.9, 4 H); 3.62 (t, J ¼ 7.7, 2 H); 1.69 –
1.56 (m, 2 H); 1.40 – 1.20 (m, 18 H); 0.90 (t, J ¼ 6.7, 3 H). 13C-NMR: 146.7; 132.2; 122.5; 113.8; 52.4; 31.9;
29.6; 29.5; 29.4; 29.3; 27.3; 27.2; 27.0; 22.7; 14.1. Anal. calc. for C24H33Br2N: C 58.19, H 6.71, N 2.83; found:
C 58.21, H 6.76, N 2.86.
2.2. N-Alkylbis[4-(2-thienyl)phenyl]amines 4a,c,d. According to [4], from 3a,c,d (2.0 mmol) and
tributyl(2-thienyl)stannane (5.0 mmol).
N-Butyl-4-(2-thienyl)-N-[4-(2-thienyl)phenyl]benzenamine (4a): Green microcrystals (0.70 g, 90%).
1
M.p. 136 – 1378. H-NMR: 7.56 (d, J ¼ 8.6, 4 H); 7.26 – 7.24 (m, 4 H); 7.10 – 7.05 (m, 6 H); 3.77 (t, J ¼ 7.7,
2 H); 1.76 – 1.67 (m, 2 H); 1.48 – 1.39 (m, 2 H); 0.99 (t, J ¼ 7.3, 3 H). 13C-NMR: 147.1; 144.5; 128.0; 127.6;
126.9; 123.8; 122.0; 121.1; 52.1; 29.6; 20.3; 14.0. Anal. calc. for C24H23NS2: C 73.99, H 5.95, N 3.60; found:
C 73.91, H 5.90, N 3.57.
1
N-Nonyl-4-(2-thienyl)-N-[4-(2-thienyl)phenyl]benzenamine (4c): Blue oil (0.75 g, 82%). H-NMR:
7.54 (d, J ¼ 8.7, 4 H); 7.26 – 7.22 (m, 4 H); 7.09 – 7.03 (m, 6 H); 3.74 (t, J ¼ 7.7, 2 H); 1.85 – 1.62 (m, 2 H);
1.35 – 1.29 (m, 12 H); 0.90 (t, J ¼ 6.8, 3 H). 13C-NMR: 147.0; 144.4; 127.9; 127.5; 126.9; 123.7; 121.9; 121.0;
52.3; 31.8; 29.6; 29.4; 29.2; 27.4; 27.1; 22.7; 14.1. Anal. calc. for C29H33NS2: C 75.77, H 7.24, N 3.05; found: C
75.40, H 7.33, N 3.16.
N-Dodecyl-4-(2-thienyl)-N-[4-(2-thienyl)phenyl]benzenamine (4d): Blue oil (0.79 g, 79%).
1H-NMR: 7.54 (d, J ¼ 8.7, 4 H); 7.24 – 7.22 (m, 4 H); 7.10 – 7.05 (m, 6 H); 3.74 (t, J ¼ 7.7, 2 H ) ; 1.83 –
1.62 (m, 2 H); 1.40 – 1.26 (m, 18 H); 0.89 (t, J ¼ 6.7, 3 H). 13C-NMR: 146.5; 144.2; 128.2; 128.0; 126.9;
123.9; 122.1; 121.2; 52.8; 31.9; 29.6; 29.6; 29.5; 29.4; 29.3; 27.2; 27.0; 22.7; 14.1. Anal. calc. for C32H39NS2: C
76.59, H 7.83, N 2.79; found: C 76.72, H 7.87, N 2.91.
2.3. N-Alkylbis[4-(furan-2-yl)phenyl]amine (5a,b). According to [4], from 3a,b (2.0 mmol) and
tributyl(furan-2-yl)stannane (5.0 mmol).
N-Butyl-4-(furan-2-yl)-N-[4-(furan-2-yl)phenyl]benzenamine (5a): Yellow microcrystals (0.58 g,
1
82%). M.p. 98 – 998. H-NMR: 7.60 (d, J ¼ 8.8, 4 H); 7.46 (d, J ¼ 1.8, 2 H); 7.06 (d, J ¼ 8.8, 4 H); 6.55
(d, J ¼ 3.3, 2 H); 6.48 – 6.46 (m, 2 H); 3.76 (t, J ¼ 7.7, 2 H); 1.75 – 1.65 (m, 2 H); 1.46 – 1.37 (m, 2 H); 0.97
(t, J ¼ 7.3, 3 H). 13C-NMR: 154.1; 146.9; 141.4; 124.9; 124.2; 120.9; 111.6; 103.5; 52.1; 29.6; 20.3; 13.9.
Anal. calc. for C24H23NO2: C 80.64, H 6.49, N 3.92; found: C 80.54, H 6.56, N 3.98.
4-(Furan-2-yl)-N-[4-(furan-2-yl)phenyl]-N-heptylbenzenamine (5b): Green oil (0.72 g, 90%).
1H-NMR: 7.59 (d, J ¼ 8.8, 4 H); 7.43 (dd, J ¼ 1.8, 0.7, 2 H); 7.04 (d, J ¼ 8.9, 4 H); 6.54 (dd, J ¼ 3.3, 0.7,
2 H); 6.46 – 6.45 (m, 2 H); 3.73 (t, J ¼ 7.7, 2 H); 1.72 – 1.67 (m, 2 H); 1.33 – 1.29 (m, 8 H); 0.89 (t, J ¼ 6.8,
3 H). 13C-NMR: 154.2; 146.9; 141.4; 124.9; 124.2; 120.9; 111.6; 103.5; 52.3; 31.9; 29.1; 27.5; 27.1; 22.6; 14.1.
Anal. calc. for C27H29NO2: C 81.17, H 7.32, N 3.51; found: C 81.27, H 7.37, N 3.59.
2.4. N-Butylbis[4-(pyridin-2-yl)phenyl]amine (¼ N-Butyl-4-(pyridin-2-yl)-N-[4-(pyridin-2-yl)phe-
nyl]benzenamine (6a). According to [4], from 3a (2.0 mmol) and tributyl(pyridin-2-yl)stannane
1
(5.0 mmol): 6a (0.45 g, 60%). Deep blue oil. H-NMR: 8.63 – 8.61 (m, 2 H); 7.93 – 7.88 (m, 4 H); 7.69 –
7.62 (m, 4 H); 7.14 – 7.09 (m, 6 H); 3.77 (t, J ¼ 7.7, 2 H); 1.70 – 1.65 (m, 2 H); 1.40 – 1.24 (m, 2 H); 0.91
(t, J ¼ 7.3, 3 H). 13C-NMR: 157.1; 149.5; 148.4; 136.6; 132.2; 127.8; 121.3; 120.9; 119.7; 52.0; 29.6; 20.3;
13.9. Anal. calc. for C26H25N3: C 82.29, H 6.64, N 11.07; found: C 82.59, H 6.69, N 11.00.
2.5. N-Alkylbis[4-(2,3-dihydrothieno[3,4-b]-1,4-dioxin-5-yl)phenyl]amine (7a,b). According to [4],
from 3a,b (2.0 mmol) and tributyl(2,3-dihydrothieno[3,4-b]-1,4-dioxin-5-yl)stannane (5.0 mmol).

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N-Butyl-4-(2,3-dihydrothieno[3,4-b]-1,4-dioxin-5-yl)-N-[4-(2,3-dihydrothieno[3,4-b]-1,4-dioxin-5-
yl)phenyl]benzenamine (7a): Blue oil (0.87 g, 86%). 1H-NMR: 7.66 (d, J ¼ 8.7, 4 H); 7.06 (d, J ¼ 8.7, 4 H);
6.27 (s, 2 H) 4.29 – 4.27 (m, 4 H); 4.24 – 4.22 (m, 4 H); 3.75 (t, J ¼ 7.6, 2 H); 1.74 – 1.68 (m, 2 H); 1.45 – 1.37
(m, 2 H); 0.98 (t, J ¼ 7.3, 3 H). 13C-NMR: 146.2; 142.3; 137.3; 127.0; 126.3; 120.9; 117.6; 96.5; 64.7; 64.5;
52.1; 29.6; 20.3; 14.0. Anal. calc. for C28H27NO4S2: C 66.51, H 5.38, N 2.77; found: C 66.55, H 5.42, N 2.79.
4-(2,3-Dihydrothieno[3,4-b]-1,4-dioxin-5-yl)-N-[4-(2,3-dihydrothieno[3,4-b]-1,4-dioxin-5-yl)phe-
1
nyl]-N-heptylbenzenamine (7c): Blue oil (0.85 g, 74%). H-NMR: 7.62 (d, J ¼ 8.7, 4 H); 7.02 (d, J ¼ 8.7,
4 H); 4.30 – 4.28 (m, 4 H); 4.25 – 4.23 (m, 4 H); 3.72 (t, J ¼ 7.7, 2 H); 1.73 – 1.62 (m, 2 H); 1.35 – 1.28 (m,
12 H); 0.90 (t, J ¼ 6.8, 3 H). 13C-NMR: 146.4; 142.4; 137.4; 127.2; 126.3; 121.0; 117.8; 96.6; 64.9; 64.6; 52.5;
32.0; 29.8; 29.6; 29.4; 27.6; 27.4; 22.8; 14.3. Anal. calc. for C33H37NO4S2: C 68.84, H 6.48, N 2.43; found: C
68.98, H 6.72, N 2.52.
2.6. N-Butylbis[4-(oxazol-2-yl)phenyl]amine (¼ N-Butyl-4-(oxazol-2-yl)-N-[4-(oxazol-2-yl)phenyl]-
benzenamine; 8a). According to [4], from 3a (0.77 g, 2.0 mmol) and tributyl(oxazol-2-yl)stannane
(1.79 g, 5.0 mmol): 8a (0.57 g, 80%). Yellow oil. 1H-NMR 7.92 (d, J ¼ 8.7, 4 H); 7.63 (d, J ¼ 0.7, 2 H); 7.17
(d, J ¼ 0.7, 2 H); 7.08 (d, J ¼ 8.7, 4 H); 3.76 (t, J ¼ 7.7, 2 H); 1.70 – 1.63 (m, 2 H); 1.42 – 1.29 (m, 2 H); 0.91
(t, J ¼ 7.2, 3 H). 13C-NMR: 161.0; 149.0; 138.0; 128.2; 127.6; 120.8; 120.7; 52.0; 29.6; 20.2; 13.9. Anal. calc.
for C22H21N3O2: C 73.52, H 5.89, N 11.69; found: C 73.59, H 5.96, N 11.88.
3. Oxidative Polymerization. The electrosyntheses and studies of the polymer films were performed
with an Ecochemie-Autolab potentiostat/galvanostat, model PGSTAT20, driven by a computer. Results
were analyzed by the GPES program (general purpose electrochemical system). Cyclic voltammetry
(CV) was used for the electrochemical measurements.
The polymer film was synthesized directly on the Pt or ITO (indium tin oxide) electrode, which was
used as a working electrode. The Ag-wire served as a pseudoreference electrode, and a Pt-spiral was
employed as an auxiliary electrode.
REFERENCES
[1] F. Zhang, M. Jonforsen, D. M. Johansson, M. R. Andersson, O. Inganas, Synth. Met. 2003, 138, 555.
[2] R. Zheng, M. Haussler, H. Dong, J. W. Y. Lam, B. Z. Tang, Macromolecules 2006, 39, 7973.
[3] W. Y. Wong, G. J. Zhou, X. M. Yu, H. S. Kwok, Z. Lin, Adv. Funct. Mater. 2007, 17, 315.
[4] J. Cabaj, K. Idzik, J. Sołoducho, A. Chyla Tetrahedron 2006, 62, 758.
[5] W. A. Doak, C. Knessl, H. Labaziewicz, S. E. OꢁConnor, L. Pup, G. Putz, M. Schranz, R. I. Walter, L.
Yang, N. H. Werstuik, Can. J. Chem./Rev. Can. Chim. 1985, 63, 3371.
[6] C. L. Gaupp, J. R. Reynolds, Macromolecules 2003, 36, 6305.
[7] J. Cremer, C. A. Briehn, Chem. Mater. 2007, 19, 4155.
[8] J. Doskocz, M. Doskocz, S. Roszak, J. Sołoducho, J. Leszczynski, J. Phys. Chem. A 2006, 110, 13989.
[9] J. Cabaj, J. Doskocz, J. Sołoducho, A. Chyla, Heterocycles 2006, 68, 137.
[10] J. Doskocz, J. Sołoducho, J. Cabaj, M. Łapkowski, S. Golba, K. Palewska, Electroanalysis 2007, 19,
1394.
[11] A. Sapp, G. A. Sotzing, J. R. Reynolds, Chem. Mater. 1998, 10, 2101.
Received October 25, 2007