www.afm-journal.de
2:1) as eluent to afford 4 (516 mg, 55.2%) as a white powder. 1
www.MaterialsViews.com
(
H
NMR (400 MHz, CDCl , δ): 8.29–8.16 (m, 4 H), 8.11 (t, J = 5.0 Hz,
3
2
7
H), 8.07–7.99 (m, 3 H), 7.86 (d, J = 7.7 Hz, 1 H), 7.68–7.58 (m, 3 H),
.54–7.50 (m, 2 H), 2.10–1.93 (m, 4 H), 1.21–1.03 (m, 12 H), 0.84–0.75
1
3
(m, 10 H). C NMR (100 MHz, CDCl , δ): 153.35, 150.53, 140.42,
3
139.93, 139.24, 138.10, 131.56, 131.01, 130.64, 130.11, 129.53, 128.63,
127.64, 127.49, 127.48, 126.29, 126.09, 125.36, 125.27, 125.21, 125.11,
124.98, 124.86, 124.69, 121.21, 121.18, 119.78, 55.60, 40.30, 31.56,
29.70, 23.91, 22.64, 14.08.
Synthesis
tetramethyl-1,3,2-dioxaborolane (5): A flask charged with 4 (400 mg,
.33 mmol), bis(pinacolato)diborane (100 mg, 0.39 mmol), potassium
acetate (121 mg, 1.24 mmol), Pd(dppf) Cl2 (14 mg, 0.01 mmol), and
of
2-(9,9-Dihexyl-7-(pyren-1-yl)-9H-fluoren-2-yl)-4,4,5,5-
0
2
1
5 mL of anhydrous dioxane was degassed for 15 min. After the mixture
was stirred at 95 °C for 12 h, it was cooled to room temperature and
then poured into ice water (100 mL). The mixture was then extracted
with CHCl , and the combined organic layers were dried over anhydrous
3
MgSO . After the solvent was evaporated, the residue was purified by
4
chromatography using silica gel (hexane: CHCl = 2:1) to afford 5 (353
3
1
mg, 81.8%) as a white solid. H NMR (400 MHz, CDCl , δ) : 8.29–8.16
m, 4H), 8.15–8.08 (m, 3H), 8.07–8.00 (m, 2 H), 7.96–7.82 (m, 2 H),
3
Figure 7. The increase of the ASE threshold as a function of the annealing
(
temperature for 90 nm thick films (TrFPy and TrF2Py).
7
1
.84 (d, J = 2.8 Hz, 2 H), 7.66–7.61 (m, 2 H), 2.07 (d, J = 7.3 Hz, 4 H),
.44 (s, 12 H), 1.21–1.07 (m, 12 H), 0.81 (t, J = 6.9 Hz, 10 H). 13C NMR
(
100 MHz, CDCl , δ): 151.49, 150.29, 143.90, 140.40, 140.15, 138.33,
performing on them. The lowest ASE threshold for neat films
3
was found to be 180 nJ pulse − for TrFPy and 101 nJ pulse for
1
−1
133.92, 131.55, 131.02, 130.57, 129.31, 128.96, 128.64, 127.69, 127.49,
127.42, 127.41, 126.06, 125.44, 125.40, 125.14, 125.10, 124.98, 124.82,
124.69, 120.13, 119.20, 83.79, 55.32, 40.26, 31.57, 29.74, 25.01, 23.88,
22.65, 14.11.
TrF2Py. A tunable optical window of 13 nm for TrF2Py (from
4
33to 445 nm) was achieved by controlling the thickness, and
the ASE was even detectable for a thin film of 25 nm. 1D DFB
lasing (50% fill factor, pumped source at 355 nm) demonstrated
Synthesis of 1-(7′-Bromo-9,9,9′,9′-tetrahexyl-9H,9′H-[2,2′-bifluoren]-7-yl)
pyrene (6): A flask charged with 5 (400 mg, 0.60 mmol), 2,7-dibromo-
lasing threshold of 9.3 kW cm− and 7.3 kW cm for TrFPy (at
2
−2
9,9-dihexyl-9H-fluorene (3) (0.88 g, 1.80 mmol), Pd(PPh3)4 (23 mg,
0
.02 mmol ), and K CO3 (20 mg) in toluene/water (2:1, 60 mL) was
2
4
57 nm) and TrF2Py lasers (at 451 nm), respectively. The lasing
degassed for 15 min. After being refluxed for 24 h, it was cooled to
room temperature and then extracted with CHCl3 (25 mL × 3). The
organic layer was washed with water, brine and dried with anhydrous
output wavelength could be fine-tuned by changing the periods
of the gratings. In comparison to a slightly enhanced ASE
threshold for TrFPy, the ASE for TrF2Py was found to be rela-
tively robust against annealing in an ambient condition, which
was less affected by heating up to 160 °C. The result was con-
sistent with an absence of scattering-induced losses. However,
the easier tendency of oxidation for TrF2Py in an ambient con-
dition generated a significantly raised ASE threshold (17.6-fold
relative to the as-spun films) when the annealing temperature
was increased to 200 °C. In contrast, the TrFPy films showed
excellent optical gain stability and the ASE can even be detect-
able after annealing at a very high temperature of 250 °C. These
results suggest the utilization of pyrene as building blocks for
exploring novel organic semiconductor gain media can effec-
tively improve the thermal stability while maintain excellent
lasing properties.
MgSO . The solvent was removed and the residue was purified by silica
4
gel column using hexane/CH Cl (2:1) as eluent to afford 6 (146 mg,
2
2
1
47.3%) as a white powder. H NMR (400 MHz, CDCl3, δ): 8.29–8.17 (m,
4
7
7
0
1
H), 8.14–8.08 (m, 3 H), 8.07–8.00 (m, 2 H), 7.93 (d, J = 8.1 Hz, 1 H),
.89 (d, J = 7.8 Hz, 1 H), 7.77 (d, J = 7.9 Hz, 1 H), 7.72–7.60 (m, 7 H),
.49 (d, J = 8.7 Hz, 2 H), 2.15–1.95 (m, 8 H), 1.12 (d, J = 16.1 Hz, 24 H),
13
.94–0.75 (m, 20 H). C NMR (100 MHz, CDCl , δ): 153.31, 151.93,
3
51.20, 151.18, 141.06, 140.49, 140.25, 139.99, 139.97, 139.90, 139.29,
138.36, 131.59, 131.06, 130.60, 130.05, 129.46, 128.68, 127.72, 127.50,
127.44, 127.42, 126.36, 126.27, 126.07, 125.46, 125.43, 125.16, 125.03,
24.83, 124.71, 121.55, 121.49, 121.12, 121.04, 120.14, 120.07, 119.77,
5.59, 55.42, 40.39, 40.33, 31.56, 31.50, 29.74, 29.67, 24.01, 23.79, 22.62,
2.61, 14.08, 14.05.
General Procedure for Synthesis of TrPy: The monomer 1 (229 mg,
.815 mmol), 8 (200 mg, 0.163 mmol), TBAB (50 mg, 0.155 mmol)
and Pd(PPh3)4 (62 mg) were placed in a 30 mL vessel. A mixture
1
5
2
0
of 2 M K CO3 aqueous solution (5 mL) and THF (15 mL) was added
2
to the vessel. The mixture was then irradiated at 250 W for 30 min in
microwave cavity. After the mixture was cooled to room temperature, it
was extracted with CHCl3 (25 mL × 3). The organic layer was washed
with water, brine, and dried with anhydrous MgSO4. The solvent was
removed and the residue was purified by silica gel column using hexane/
4
. Experimental Section
Materials: All reagents and solvents, unless otherwise specified,
were obtained from Aldrich, Acros, and TCI Chemical Co., and used
as received. All manipulations involving air-sensitive reagents were
performed under an atmosphere of dry nitrogen.
1
CH2Cl2 (2:1) as eluent to afford TrPy (213 mg, yield: 89.6%): H NMR
(400 MHz, CDCl3, δ): 8.60 (d, J = 8.2 Hz, 3 H), 8.40–8.30 (m, 6 H),
8.25–8.00 (m, 21H), 7.80 (s, 3 H), 7.72 (d, J = 8.0 Hz, 3 H), 3.17 (d, J
= 6.8 Hz, 6 H), 2.27 (d, J = 7.2 Hz, 6 H), 1.14–1.00 (m, 36 H), 0.82 (s,
Synthesis of 1-(7-Bromo-9,9-dihexyl-9H-fluoren-2-yl)pyrene (4): A flask
charged
with
4,4,5,5-tetramethyl-2-(pyren-1-yl)-1,3,2-dioxaborolane
1
3
(
(
(
2) (500 mg, 1.52 mmol), 2,7-dibromo-9,9-dihexyl-9H-fluorene (3)
2.25 g, 4.56 mmol), Pd(PPh3)4 (53 mg, 0.04 mmol), and K CO3
20 mg) in toluene/water (2:1, 60 mL) was degassed for 15 min. After
12 H), 0.73 (t, J = 6.5 Hz, 18 H). C NMR (100 MHz, CDCl3, δ): 153.86,
145.50, 139.56, 139.23, 138.41, 138.24, 131.62, 131.11, 130.62, 128.72,
128.61, 127.77, 127.54, 127.50, 127.45, 126.08, 125.53, 125.22, 125.16,
125.09, 124.84, 124.77, 124.74, 124.71, 55.98, 37.06, 31.97, 31.65, 29.74,
29.70, 29.62, 29.40, 24.17, 22.73, 22.44, 14.16, 14.09. MALDI-TOF-MS
2
being refluxed for 24 h, it was cooled to room temperature and then
extracted with CHCl (25 mL × 3). The organic layer was washed with
water, brine and dried with anhydrous MgSO . The solvent was removed
3
+
+
(m/z): calcd for C111H114, exact mass: M 1446.89; Found: 1446.5 (M ),
1361.2 ([M-C6H13] ).
4
+
and the residue was purified by silica gel column using hexane/CH Cl2
2
Adv. Funct. Mater. 2015, 25, 4617–4625
© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
wileyonlinelibrary.com 4623