J IRAN CHEM SOC
synthesized as previously reported [24]. N, N-dimethylfor-
Synthesis of L1 [26]
mamide was dried by distillation over CaH and methanol
2
was dried over molecular sieves and freshly distilled prior
to being used. The other materials were of common com-
mercial grade and used as received. All chemicals used
were of an analytical grade. Solvents were purified with
conventional methods.
Zn(CH COO) ·2H O (0.22 g, 1 mmol) was dissolved in
3
2
2
methanol (15 mL), and then PBI-Th (0.74 g, 2 mmol) in
THF (20 mL) were added to the solution. Then 1 mol L
-1
NaOH was added dropwise (under stirring) until the solu-
tion shows weakly acidic. After the solution was refluxed
for 6 h, the reaction system was allowed to cool to room
temperature. The precipitate was collected by filtration,
washed with dried ether many times and then dried in
vacuum at 60 ºC. A yellow solid (0.42 g, yield 80 %) was
Instruments and measurements
1
H NMR spectra were obtained in CDCl and recorded with
3
–
1
a Bruker ARX400 (400 MHz) Germany and using tetra-
methylsilane (0.00 ppm) as the internal reference. FT-IR
spectra were recorded using KBr pellets with a PerkinElmer
Spectrum One FT-IR spectrometer over the range 400–
obtained. FTIR (KBr; cm ): 3,095, 2,916 (aromatic and
vinylic C–H), 1,650 (C = N), 1,483 (C = C), 1,150 (C–
N–M), 510 (M–N). Anal. Calcd for [C H Br N O S Zn]:
3
8
30
2
6
4 2
C, 49.39; H, 3.27; Br, 17.30; N, 9.10; O, 6.93; S, 6.94; Zn,
7.08; found: C, 49.05; H, 3.46; N, 8.75.
-1
4
,000 cm . Gel permeation chromatography (GPC) analy-
ses were measured by a WATER 2414 system equipped
with a set of HT , HT and HT , l-styrayel columns with
Synthesis of L2
3
4
5
THF as eluent and polystyrene as standard. Thermogravi-
metric analyses (TGA), differential scanning calorimetry
In the same manner as described for L1, L2 affords a light
brown solid (Yield: 91 %). Anal. Calcd for C H Br N
6
(DSC) and elemental analysis were performed on Shimadzu
3
8
30
2
TGA-7 Instrument, Perkin-Elmer DSC-7 thermal analyzer
and Perkin-Elmer 2400 II instrument, respectively. UV–
visible spectra of all the polymers were taken on a Lambda
O S Co: C, 49.74; H, 3.30; Br, 17.42; Co, 6.42; N, 9.16;
4 2
O, 6.97; S, 6.99. Found: C, 49.23; H, 3.16; N, 9.24. FTIR
–
1
(KBr, cm ): 3,068, 2,903 (aromatic and vinylic C–H),
1,663 (C = N), 1,475 (C = C), 1,116 (C–N–M), 504
(M–N).
25 spectrophotometer. Photoluminescent spectra (PL) were
taken on a Perkin-Elmer LS55 luminescence spectrom-
eter with a xenon lamp as the light source. Cyclic voltam-
metry (CV) was conducted on a CHI630C electrochemical
workstation using a three electrode system, in a [Bu N]BF
Synthesis of Polymeric metal complex P1
4
4
(
0.1 M) DMF solution at a scan rate of 100 mV/s. The
The polymeric metal complex P1 was synthesized using
the Heck coupling method, according to the literature
[27]. A flask was charged with a mixture of metal com-
plex L1 (0.173 g, 0.315 mmol), 1,4-bis(octyloxy)-2,5-di-
working electrode was a glassy carbon electrode, the auxil-
iary electrode was a platinum wire electrode and a saturated
calomel electrode (SCE) was used as reference electrode.
vinylbenzene (0.122 g, 0.315 mmol), Pd(OAc) (0.0024 g,
2
Synthesis
0.012 mmol), triethylamine (3 mL), 3-o-tolyl phospine
(0.0220 g, 0.072 mmol) and DMF (8 mL). Then the flask
Synthesis of 2‑Bromo‑5‑[2‑(2′‑pyridyl)benzimidazolyl]‑3‑m
was pumped into a vacuum and purged with N . The mix-
2
ethylthiophene [25]
ture was heated at 90 ºC for 18 h under N . After that, it was
2
cooled to room temperature and filtered, then the filtrate
was poured into ethanol. The yellow precipitate was filtered
and washed with cold ethanol. The crude product was puri-
fied by dissolving in DMF and precipitating into ethanol to
afford a light yellow solid (Yield: 0.184 g, 53 %). FT-IR
(PBI-Th).
A mixture of 2, 5-dibromo-3-methylthiophene (1.27 g,
5
.0 mmol), 2-(2′-pyridyl)benzimidazole (0.99 g, 5.0 mmol),
CuI (0.081 g, 0.43 mmol), 1,10-phenanthroline (0.16 g,
.88 mmol) and K CO (1.38 g, 8.9 mmol) was suspended
–
1
0
(KBr, cm ): 3,075, 2,930, 2,851, 1,658 (C = N), 1,052 (C–
2
3
in 3.0 mL of DMF. The mixture was refluxed for 24 h and
then cooled to room temperature. The resulting brown
sticky residue was extracted with CH Cl (50 mL × 4), and
N–M), 475 (N–M). Anal. Calcd for [C H N O S Zn]: C,
6
4
70
6
6 2
67.24; H, 6.50; N, 7.13; O, 8.14; S, 5.44; Zn, 5.55. Found:
C, 66.57; H, 6.32; N, 7.02. Mn = 7.8 kg/mol, PDI = 1.49.
2
2
the organic extracts were combined, dried over MgSO and
4
purified by column chromatography (1:1 THF/hexane) to
Synthesis of Polymeric metal complex P2
obtain the crude product of Brmt as yellow powder (0.74 g
1
yield 40.2 %). H NMR (400 MHz, CDCl ): 8.57(s, 1H),
8
7
With the similar synthetic method as P1, P2 affords solid
(0.174 g, 51 %). FT-IR (KBr, cm ): 3,067, 2,915, 2,841,
1,675 (C = N), 1,096 (C–N–M), 496 (N–M). Anal. Calcd
3
–
1
.19(d, 1H), 7.86(d, 2H), 7.75–7.82(t, 1H), 7.40(s, 1H),
.27(s, 2H), 6.78 (s, 1H), 2.23(s, 3H).
1
3