ferrocenyl and the fluorenyl substituted chromophores are
1
thermally stable.
(7-Bromo-9,9-dibutyl-9H-fluoren-2-yl)-diphenylamine (7)
mixture of 9,9-dibutyl-2,7-dibromofluorene (21.8 g,
.05 mol), diphenylamine (5.07 g, 0.03 mol), bis(dibenzylide-
0
A
0
3
Conclusions
neacetone)palladium(0) (0.20 g, 0.35 mmol), bis(diphenylphos-
phino)ferrocene (0.21 g, 0.39 mmol), sodium tert-butoxide
(3.6 g, 0.0374 mol), and toluene (200 mL) was kept under
argon at 70 uC for 24 h. The mixture was cooled and poured
into 100 mL of water. The product was extracted with toluene,
and the organic phase was washed three times with water (3 6
Two novel fluorene-containing ferrocene derivatives were
13
1
designed, synthesized and characterized by H NMR,
C
NMR, HRMS and elemental analysis. The combination of
fluorene and ferrocene has resulted in compounds with large
two-photon and three-photon absorption in the IR region, as
well as excellent thermal stability up to 453 uC. The results
show that ferrocene complexes are promising candidates
for multi-photon absorbing materials. Fairly good optical
limiting behaviours were demonstrated using these two novel
chromophores.
1
00 mL), dried, and concentrated on a rotary evaporator. The
residual was transferred to a silica gel column. Elution with
hexanes resulted in a fraction containing unreacted 9,9-
dibutyl-2,7-dibromofluorene. The desired product was eluted
out with heptane as a white crystalline solid, 17.2 g, 83% yield.
1
H NMR (300 MHz, CDCl , ppm): d 7.51 (d, 1H, J 5 8.4 Hz),
3
7
6
4
.47–7.40 (m, 5H), 7.27–7.22 (m, 5H), 7.12–7.08 (m, 5H), 7.03–
.99 (m, 3H), 1.86–1.80 (m, 4H), 1.11–1.07 (m, 4H), 0.71 (t,
4
Experimental
1
3
H, J 5 7.5 Hz), 0.65–0.59 (m, 4H). C NMR (75 MHz,
, ppm): d 152.84, 151.71, 147.85, 147.54, 139.95, 134.99,
29.88, 129.17, 125.95, 123.91, 123.33, 122.64, 120.41, 120.39,
120.09, 118.99, 55.23, 39.87, 25.93, 22.93, 13.86. HRMS (ESI)
Chemicals, including 2-nitrofluorene and 2,7-dibromofluorene
were purchased from the Aldrich Chemical Co. (E)-2-((4-
vinylphenyl)vinylferrocene, 2-bromo-7-nitro-9H-fluorene and
CDCl
3
1
9
,9-dibutyl-2,7-dibromofluorene were prepared according to
1
1,16–18
+
the literature procedures.
1
carried out on silica gel 60 (230–400). H NMR spectra were
Column chromatography was
calc. for (M + H) C33
H34NBr: 523.1875, found: 523.1851.
1
3
run at either 300, 400, or 500 MHz in CDCl
3
.
C NMR
(9,9-Dibutyl-7-{(E)-2-[4-[(E)-(2-ferrocenyl-vinyl)]-phenyl]-
vinyl}-9H-fluoren-2-yl)-diphenylamine (1)
spectra were recorded either at 75 or 125 MHz in CDCl
3
.
Electrospray ionization (ESI) mass spectra were obtained on
Thermo Finnigan LCQ Advantage mass spectrometer. EI
mass spectra were measured at 70 eV. Elemental analysis was
performed by Atlantic Microlab, Inc.
(
7-Bromo-9,9-dibutyl-9H-fluoren-2-yl)-diphenylamine (1.73 g,
2
2
,5 mmol), (E)-2-((4-vinylphenyl)vinylferrocene (0.78 g,
.5 mmol), Pd(OAc) (13 mg, 0.04 mmol), P(o-tolyl)
N (2.0 mL), CH CN (20 mL) were
2
3
(
190 mg, 0.06 mmol), Et
3
3
added to a pressure tube with a plunger valve and a magnetic
bar under argon atmosphere. The resulting mixture was
refluxed for 24 h and then cooled to room temperature. The
mixture was poured into 50 mL of methanol while vigorous
stirring. The precipitate formed was collected on a filter and
washed with methanol, and crude product was separated
1
1
(
E)-2-((4-Vinylphenyl)vinylferrocene (4)
This product was synthesized with 75% yield according to
1
literature procedure. H NMR (300 MHz, CDCl
.38 (s, 4H), 6.89–6.66 (m, 3H), 5.74 (d, J 5 17.4 Hz, 1H), 5.23
d, J 5 17.4 Hz, 1H), 4.46 (s, 2H), 4.27 (s, 2H), 4.13 (s, 5H).
3
, ppm): d
7
(
1
3
C NMR (75 MHz, CDCl
3
, ppm): d 137.47, 136.56, 136.06,
by column chromatography on silica gel using CH
Cl as the
2 2
1
6
27.00, 126.53, 125.88, 125.63, 113.21, 83.29, 69.20, 69.07,
6.86.
eluent. The product was collected in 75% yield as red
1
crystalline solid. H NMR (500 MHz, CDCl
.47 (m, 6H), 7.40–7.27 (m, 6H), 7.21–7.18 (m, 6H), 7.08–7.05
(m, 4H), 6.95 (d, J 5 16.0 Hz, 1H), 6.75 (d, J 5 16.0 Hz, 1H),
3
, ppm): d 7.67–
7
1
6
2
-Bromo-9,9-dibutyl-7-nitro-9H-fluorene (10)
4
1
.54 (s, 2H), 4.22 (s, 2H) 4.21 (s, 5H), 1.96–1.86 (m, 4H), 1.19–
13
To a mechanically stirred mixture of 2-bromo-7-nitro-9H-
fluorene (2.9 g, 0.01 mol), potassium iodide (0.16 g, 0.001 mol),
potassium hydroxide (2.3 g, 0.04 mol) and DMSO (50 mL) in
ice-water bath, 1-bromobutane (4.1 g, 0.03 mol) was added
dropwise. After the addition was completed, the reaction
mixture was then stirred at room temperature for 8 h before
3
.12 (m, 4H), 0.80–0.73 (m,10H). C NMR (75 MHz, CDCl ,
ppm): d 152.38, 151.15, 147.93, 147.12, 137.01, 135.97, 135.59,
1
1
6
29.14, 128.77, 127.29, 126.87, 126.73, 126.07, 125.70, 125.63,
23.82, 123.44, 122.50, 120.52, 120.31, 119.29, 83.39, 69.25,
9.22, 69.09, 66.86, 54.89, 40.07, 26.01, 23.02, 13.90. HRMS
calc. for C H N Fe : 757.3365. Found: 757.3377. Elemental
5
3
51
1
1
1
00 mL of water was added. The reaction mixture was extracted
analysis. calc. for C H N Fe : C, 84.00; H, 6.78; N, 1.85.
5
3
51
1
1
with 200 mL of CH Cl and the combined organic layer was
2
2
Found for: C, 83.68; H, 7.08; N, 2.06.
dried over MgSO
yield) of compound 10 was collected as yellow solid. H NMR
400 MHz, CDCl , ppm): d 8.25–8.23 (dd, J 5 2.0 Hz, J
.4 Hz, 1H), 8.17 (d, J 5 2.0 Hz, 1H), 7.75 (d, J 5 8.4 Hz, 1H),
.63 (d, J 5 8.4 Hz), 7.52–7.51 (m, 2H), 2.05–1.94 (m, 4H),
4
. After removing the solvent, 3.5 g (89%
1
9
7
,9-Dibutyl-2-{(E)-2-[4-[(E)(2-ferrocenyl-vinyl)]-phenyl]-vinyl}-
-nitro-9H-fluorene (2)
(
3
1
2
5
8
7
1
This compound was synthesized in 84% yield by the same
1
procedure as used for the preparation of compound 1.
1
3
.12–1.00 (m, 4H), 0.66 (t, J 5 7.6 Hz, 6H), 0.55 (m, 4H).
, ppm): d 154.40, 151.35, 147.51, 146.51,
38.29, 136.57, 132.45, 123.39, 122.68, 120.00, 118.22, 95.54,
C
H
NMR (75 MHz, CDCl
3
NMR (300 MHz, CDCl , ppm): d 8.25 (d, J 5 8.4 Hz, 1H),
3
1
5
8.19 (s, 1H), 7.75 (d, J 5 8.4 Hz, 2H), 7.57–7.13 (m, 8H), 6.86
(d, J 5 16.0 Hz, 1H), 6.59 (d, J 5 16.0 Hz, 1H), 4.61 (s, 2H),
+
5.80, 39.75, 25.84, 22.84, 13.72. MS (m/z): 401, 403 (M ).
3
492 | J. Mater. Chem., 2005, 15, 3488–3493
This journal is ß The Royal Society of Chemistry 2005