Journal of Materials Chemistry C
Paper
The mixture was stirred at 30 1C overnight. The reaction mixture (s, 6H). 13C NMR (100 MHz, CDCl3) d = 158.45, 155.47, 154.20,
was concentrated under vacuum, and the residue was purified by 147.06, 143.07, 141.09, 131.73, 129.54, 128.22, 121.20, 115.12,
column chromatography (silica gel. petroleum ether/CH2Cl2
=
111.23, 99.96, 91.17, 66.75, 57.93, 50.33, 14.69, 14.59. MALDI-
2: 1, v/v). The red band was collected, and the solvent was HRMS: m/z calcd for [C33H32N5OBF2Fe]+ m/z = 619.2017; found:
removed under reduced pressure to give the product as a red m/z = 619.2028.
solid. Yield: 280.0 mg (90.4%). M.p. 168.7–170.2 1C. 1H NMR
Synthesis of complex FcB-2
(400 MHz, CDCl3) d 7.17 (d, J = 8.0 Hz, 2H), 7.07 (d, J = 8.0 Hz,
2H), 4.24 (t, J = 4.0 Hz, 2H), 3.69 (t, J = 4.0 Hz, 2H), 2.65 (s, 6H),
1.45 (s, 6H). MALDI-HRMS: m/z calcd for [C21H20N5OBF2I2]+ m/z =
660.9804; found: m/z = 660.9817.
Complex FcB-2 was prepared by a similar procedure to that
used for complex FcB-1, with ethylnylferrocene (21.0 mg,
0.1 mmol) and B-2 (66 mg, 0.1 mmol) as the starting materials,
instead of B-1. Complex FcB-1 was obtained as a deep red solid
65.3 mg, yield: 73.6%. M.p. 235.8–237.6 1C. 1H NMR (400 MHz,
CDCl3) d 7.63 (s, 1H), 7.15 (d, J = 8.0 Hz, 2H), 7.02 (d, J = 8.0 Hz,
2H), 4.81 (t, J = 8.0 Hz, 4H), 4.46 (t, J = 8.0 Hz, 2H), 4.39 (s, 2H),
4.13 (s, 5H),2.63 (s, 6H), 1.39 (s, 6H). 13CNMR (100 MHz, CDCl3)
d = 158.78, 156.86, 145.47, 141.06, 131.68, 129.72, 127.96,
116.65, 106.58, 96.08, 85.66, 68.84, 52.91, 29.50, 18.02, 16.09.
MALDI-HRMS: m/z calcd for [C33H30N5OBF2FeI2]+ m/z = 870.9950;
found: m/z = 870.9945.
Synthesis of complex B-3
Under an Ar atmosphere, to a solution of 4-ethynylbenzaldehyde
8 (400.0 mg, 3.0 mmol) and 2,4-dimethylpyrrole (672 mg,
7.0 mmol) in CH2Cl2 (250 mL) was added trifluoroacetic acid
(2.3 mL, 0.034 mmol). The mixture was stirred at RT for 1 h then
p-chloranil (756.0 mg, 3.0 mmol) was added. The mixture was
stirred at RT for another 1 h. NEt3 (5.26 g, 52.0 mmol, 7.2 mL) was
added, and the mixture was stirred for 10 min. Then BF3ꢀOEt2
(8.02 g, 55.3 mmol) was added via a syringe and the mixture was
stirred for another 10 min. The reaction mixture was washed with
water (4 ꢁ 60 mL) and dried with anhydrous Na2SO4. The solvent
was removed under vacuum and the residue was purified by
chromatography (silica gel, petroleum ether/CH2Cl2 = 1 : 1, v/v) to
give compound B-3 as an orange solid. Yield: 320 mg (28.9%).
Synthesis of complex FcB-3
Iodoferrocene (62.4 mg, 0.2 mmol) was added to a deaerated
solution of B-3 (69.6 mg, 0.2 mmol) in THF (15 mL) and
triethylamine (5 mL) (deoxygenated by Ar for 15 min). After
the mixture was stirred for 10 min, [PdCl2(PPh3)2] (14.0 mg,
0.02 mmol) and CuI (3.8 mg, 0.02 mmol) were added into the
solution, then the mixture was refluxed for 8 h. After cooling
to RT, the reaction mixture was poured into water, and the
aqueous phase was extracted with CH2Cl2 (50 mL). The com-
bined organic extracts were washed with water (50 mL) and
then brine (50 mL) and dried over anhydrous Na2SO4. The
mixture was filtered, concentrated under reduced pressure,
and purified by chromatography (silica gel; CH2Cl2/petroleum
ether = 1/4, v/v) to give a deep-red solid. Yield: 30.4 mg (28%).
1H NMR (400 Mz, CDCl3) d 7.62 (d, J = 8.0 Hz, 2H), 7.24 (d, J =
4.0 Hz, 2H), 5.99 (s, 2H), 4.53 (t, J = 4.0 Hz, 2H), 4.28 (s, 7H), 2.56
(s, 6H), 1.44 (s, 6H). MALDI-HRMS: calcd [C31H27BF2 FeN2]+
m/z = 532.1585, found, m/z = 532.1611.
1
M.p. 243.1–245.4 1C. H NMR (400 MHz, CDCl3): d 7.62 (d, J =
8.0 Hz, 2H), 7.26 (d, J = 8.0 Hz, 2H), 5.99 (s, 2H), 3.18 (s, 1 H), 2.56
(s, 6H), 1.40 ppm (s, 6H). TOF HRMS EI+: calcd [C21H19BN2F2]
m/z = 348.1609; found, m/z = 348.1617.
Synthesis of complex FcB-0
Under an Ar atmosphere, ethylnylferrocene (21.0 mg, 0.1 mmol)
and 3 (20 mg, 0.1 mmol) were dissolved in a mixed solvent
CHCl3/MeOH/H2O (8 mL, 6: 1: 1, v/v). Then CuSO4ꢀ5H2O (7.5 mg)
and sodium ascorbate (11.5 mg) were added. The resulting
mixture was stirred at 25 1C for 16 h. Then the reaction mixture
was washed with water and extracted with CH2Cl2 (3 ꢁ 50 mL).
The organic layer was dried over anhydrous Na2SO4 and
evaporated under reduced pressure. The crude product was
purified by column chromatography (silica gel, CH2Cl2) to give
a red solid. 18.0 mg, yield: 43.9%. M.p. 132.5–134.8 1C. 1H NMR
(400 MHz, CDCl3) d 7.66 (s, 1H), 7.32 (t, J = 16 Hz, 2H), 7.01
(t, J = 16 Hz, 1H), 6.91 (d, J = 8.0 Hz, 2H), 4.78 (t, J = 8.0 Hz, 2H),
4.72 (s, 2H), 4.40 (t, J = 8.0 Hz, 2H), 4.30 (s, 2H), 4.07 (s, 5H).
TOF HRMS EI+: calcd [C20H19N3OFe] m/z = 373.0878, found,
m/z = 373.0871.
Nanosecond time-resolved transient difference absorption
spectroscopy
The nanosecond time-resolved transient absorption spectra
were recorded on an LP920 laser flash photolysis spectrometer
(Edinburgh Instruments, UK). The samples were excited using a
nanosecond pulsed laser (Opotech, wavelength tunable in the
range of 410–2400 nm), and the transient signals were recorded
on a Tektronix TDS 3012B oscilloscope. All samples in flash
photolysis experiments were deaerated with nitrogen for ca. 15 min
before measurement.
Synthesis of complex FcB-1
Complex FcB-1 was prepared by a similar procedure to that
used for complex FcB-0, with ethylnylferrocene (21.0 mg, 0.1 mmol)
and B-1 (44 mg, 0.1 mmol) as the starting materials, instead of 3.
Spectroelectrochemical studies
Complex FcB-1 was obtained as a red solid 48.0 mg, yield: 77.4%. Spectroelectrochemical fluorescence measurements were per-
M.p. 211.8–212.6 1C. 1H NMR (400 MHz, CDCl3) d 7.57(s, 1H), 7.17 formed using a spectro-electrochemical quartz cell (path-length
(d, J = 8.0 Hz, 2H), 7.00 (d, J = 8.0 Hz, 2H), 5.96 (s, 2H), 4.98 (s, 2H), of 1.0 mm) with a three-electrode system: light transparent
4.78 (s, 2H), 4.54 (s, 2H), 4.42 (s, 2H), 4.25 (s, 5H), 2.54 (s, 6H), 1.39 platinum gauze (100 mesh, 7.0 ꢁ 5.0 mm) as a working
This journal is ©The Royal Society of Chemistry 2015
J. Mater. Chem. C