Supporting Information
Investigation of Mizoroki-Heck Coupling Polymerization as a Catalyst-Transfer
Condensation Polymerization for Synthesis of Poly(p-phenylenevinylene).
MASATAKA NOJIMA, RYOSUKE SAITO, YOSHIHIRO OHATA, TSUTOMU
YOKOZAWA*
Department of Material and Life Chemistry, Kanagawa University 3-27-1 Rokkakubashi,
Kanagawa-ku, Yokohama 221-8686, Japan
Synthesis of 1,4-Bis[(2-ethylhexyl)oxy]benzene (4).
Hydroquinone 3 (10.14 g, 92.1 mmol) was added to a suspension of KOH powder (41.60
g, 741.0 mmol) in dry DMSO (166 mL) at room temperature, and the whole was stirred at
room temperature for 1 h. 1-Bromo-2-ethylhexane (43 mL, 249.0 mmol) was added, and
the reaction mixture was stirred for 20 h and finally poured into ice water. The aqueous
layer was extracted with hexane, and the combined organic layers were dried over
anhydrous MgSO4. After concentration in vacuo, ethyl acetate was added, and the
solution was washed with water and saturated aqueous NH4Cl, and then dried over
anhydrous MgSO4. The solvent and excess 1-bromo-2-ethylhexane were removed to
afford 3 as a light yellow oil (31.22 g, 100%). 1H NMR (600 MHz, CDCl3) δ 6.82 (s, 4
H), 3.79 (dd, J = 5.8 and 11.7 Hz, 2 H), 3.77 (dd, J = 6.2 and 12.0 Hz, 2 H), 1.71-1.64 (m,
1
2 H), 1.51-1.30 (m, 16 H), 0.93-0.89 (m, 12 H);
13
C NMR (150 MHz, CDCl3) δ 153.4,
115.4, 71.2, 39.5, 30.5, 29.1, 23.8, 23.1, 14.1, 11.1.
Synthesis of 1,4-Bis[(2-ethylhexyl)oxy]-2,5-diiodobenzene (5).
Dialkoxybenzene 4 (15.0 g, 44.9 mmol), KIO3 (3.87 g, 18.1 mmol), and I2 (13.2 g, 52.1
mmol) were added to a stirred solution of acetic acid (275 mL), 96% H2SO4 (5.0 mL),
and H2O (20 mL). The reaction mixture was refluxed for 16 h and then cooled to room
temperature. Aqueous Na2SO4 (20 wt%) was added until the brown color of iodine
disappeared, and then the mixture was extracted with hexane. The combined organic
layers were filtered through Celite, dried over anhydrous MgSO4, and concentrated in
vacuo. The residue was purified by means of column chromatography (SiO2, hexane) to
afford 4 as a slightly yellow oil (12.56 g, 48%). 1H NMR (600 MHz, CDCl3) δ 7.16 (s, 2
H), 3.82 (dd, J = 5.4 and 9.4 Hz, 2 H), 3.80 (dd, J = 5.4 and 9.1 Hz, 2 H), 1.76-1.70 (m, 2
H), 1.58-1.26 (m, 16 H), 0.95-0.87 (m, 12 H);
13
C NMR (126 MHz, CDCl3) δ 152.8,
122.3, 86.0, 72.3, 39.4, 30.5, 29.0, 23.9, 23.0, 14.1, 11.2.
Synthesis of 2,5-Bis[(2-ethylhexyl)oxy]-4-iodobenzaldehyde (6).
A round-bottomed flask equipped with a three-way stopcock was heated under reduced
pressure, and then cooled to room temperature under an argon atmosphere.
Diiodobenzene 6 (11.02 g, 18.8 mmol) was placed in the flask, and the atmosphere in the
flask was replaced with argon. Dry Et2O (35 mL) was added to the flask via a syringe,
and the mixture was stirred at 0 oC. A solution of n- butyllithium (1.6 M solution in
2
hexane, 11.5 mL, 18.7 mmol) in dry Et2O (23 mL) was added dropwise via a syringe, and
stirring was continued at 0 oC for 5 minutes. A solution of dry DMF (2.3 mL, 29.7 mmol)
in dry Et2O (2.0 mL) was added via a syringe and the reaction mixture was stirred for 2 h
at room temperature. Then, the reaction was quenched with 1 M hydrochloric acid, and
the aqueous layer was extracted with diethyl ether. The combined organic layers were
washed with saturated aqueous NaHCO3 and brine, dried over anhydrous MgSO4, and
concentrated in vacuo. The residue was purified by means of column chromatography
(SiO2, hexane/CH2Cl2 = 5/1) to afford 6 as an orange oil (7.85 g, 85%).1H NMR (500
MHz, CDCl3) δ 10.43 (s, 1 H), 7.47 (s, 1 H), 7.18 (s, 1 H), 3.93-3.87 (m, 4 H), 1.79-1.72
(m, 2 H), 1.59-1.28 (m, 16 H), 0.95-0.89 (m, 12 H);
13
C NMR (126 MHz, CDCl3) δ
189.2, 155.9, 152.2, 125.1, 124.3, 108.4, 96.7, 72.0, 71.7, 39.5, 39.3, 30.6, 30.5, 29.04,
29.01, 23.94, 23.02, 22.97, 14.08, 14.04, 11.17, 11.15.
Synthesis of 1,4-Bis[(2-ethylhexyl)oxy]-2-iodo-5-vinylbenzene (1).
A round-bottomed flask equipped with a three-way stopcock was heated under reduced
pressure, and then cooled to room temperature under an argon atmosphere.
Methyltriphenylphosphonium bromide (2.18 g, 6.09 mmol) was placed in the flask, and
the atmosphere in the flask was replaced with argon. Dry THF (34 mL) was added to the
flask, and the mixture was stirred at 0 oC. A solution of n-butyllithium (1.6 M solution in
hexane, 3.7 mL, 6.1 mmol) was added dropwise via a syringe, and stirring was continued
at 0 oC for 20 minutes. A solution of 4-iodobenzaldehyde 6 (1.95 g, 4.00 mmol) in dry
THF (15.0 mL) was added via a syringe, and the reaction mixture was refluxed for 0.5 h
and then cooled to room temperature. The reaction was quenched with water, and the
3
aqueous layer was extracted with Et2O. The combined organic layers were washed with
water, dried over anhydrous MgSO4, and concentrated in vacuo. The residue was purified
by means of column chromatography (SiO2, hexane) to afford 1 as a yellow oil (1.57 g,
38%). 1H NMR (600 MHz, CDCl3) δ 7.25 (s, 1 H), 6.97 (dd, J = 11.0 and 17.9 Hz, 1 H),
6.90 (s, 1 H), 5.74 (dd, J = 1.03 and 17.9 Hz, 1 H), 5.26 (dd, J = 1.03 and 11.0 Hz, 1 H),
3.89-3.85 (m, 2 H), 3.82-3.78 (m, 2 H), 1.77-1.70 (m, 2 H), 1.59-1.28 (m, 16 H),
0.97-0.88 (m, 12 H);
13
C NMR (150 MHz, CDCl3) δ 152.1, 151.1, 131.3, 127.6, 123.3,
114.5, 109.5, 85.8, 72.1, 71.6, 39.6, 39.5, 30.59, 30.56, 29.10, 29.06, 23.99, 23.96, 23.05,
23.02, 14.11, 14.06, 11.24, 11.16.
Synthesis of 2,5-Dibromo-1,4-bis[(2-ethylhexyl)oxy]benzene (8).
Compound 8 (9.25 g, 18.7 mmol) was obtained in 100% yield from 7 (5.00 g, 18.7 mmol)
in a similar manner to that described for the synthesis of 4 from 3.
1
H NMR (600 MHz, CDCl3) δ 7.08 (s, 4 H), 3.81 (m, 2 H), 1.78-1.71 (m, 2 H), 1.61-1.23
(m, 16 H), 0.99-0.85 (m, 12 H); 13C NMR (126 MHz, CDCl3) δ 150.2, 1182, 111.0, 72.5,
39.4, 30.4, 29.0, 23.8, 23.0, 14.1, 11.0.
Synthesis of 4-Bromo-2,5-bis[(2-ethylhexyl)oxy]benzaldehyde (9).
A round-bottomed flask equipped with a three-way stopcock was heated under reduced
pressure, and then cooled to room temperature under an argon atmosphere.
Dibromobenzene 8 (8.51 g, 17.3 mmol) was placed in the flask, and the atmosphere in the
flask was replaced with argon. Dry THF (110 mL) was added to the flask via a syringe,
4
and the mixture was stirred at -78 oC. n-Butyllithium (2.7 M solution in hexane, 8.3 mL,
22.0 mmol) was added dropwise via a syringe, and stirring was continued at -78 oC for 1
h. The reaction temperature was raised to -30 °C, and dry DMF (2.1 mL, 27.6 mmol) was
added via a syringe. The reaction mixture was stirred at –30 oC for 1 h and at room
temperature overnight. The reaction was quenched with 1 M hydrochloric acid, and the
aqueous layer was extracted with diethyl ether. The combined organic layers were
washed with saturated aqueous NaHCO3 and brine, dried over anhydrous MgSO4, and
concentrated in vacuo. The residue was purified by means of column chromatography
(SiO2, hexane/CH2Cl2 = 5/1) to afford 9 as a slightly yellow oil (6.22 g, 82%).1H NMR
(600 MHz, CDCl3) δ10.42 (s, 1 H), 7.31 (s, 1 H), 7.24 (s, 1 H), 3.93-3.89 (m, 4 H),
1.79-1.74 (m, 2 H), 1.58-1.24 (m, 16 H), 0.96-0.87 (m, 12 H);
13
C NMR (126 MHz,
CDCl3) δ 188.9, 155.9, 150.0, 124.2, 121.1, 118.3, 110.3, 72.1, 72.7, 39.4, 39.3, 30.5,
30.4, 29.03, 28.99, 23.93, 23.87, 22.99, 22.96, 14.05, 14.03, 11.12.
Synthesis of 2-Bromo-1,4-bis[(2-ethylhexyl)oxy]- 5-vinylbenzene (2).
Compound 2 (1.08 g, 2.46 mmol) was obtained in 82% yield from 9 (1.33 g, 3.00 mmol)
in a similar manner to that described for the synthesis of 1 from 6.
1
H NMR (600 MHz, CDCl3) δ 7.05 (s, 1 H), 7.00 (s, 1 H), 6.97 (dd, J = 11.0 and 17.8 Hz,
1 H), 5.72 (dd, J = 1.1 and 17.8 Hz, 1 H), 5.27 (dd, J = 1.1 and 11.0 Hz, 1 H), 3.90-3.85
(m, 2 H), 3.83-3.78 (m, 2 H), 1.77-1.71 (m, 2 H), 1.58-1.29 (m, 16 H), 0.96-0.89 (m, 12
H); 13C NMR (150 MHz, CDCl3) δ 150.8, 149.7, 131.1, 126.6, 117.4, 114.4, 111.9, 111.2,
72.4, 71.6, 39.52, 39.51, 30.59, 30.49, 29.08, 29.06, 23.98, 23.89, 23.04, 23.01, 14.08,
14.06, 11.18, 11.15.
5
1200
3000
4000
1400
2230.17 (H/Br)
2200
2400
1600
1800
2000
2320.27 (Tolyl/Br)
2152.27 (H/H)
2230.17 (H/Br)
1961.98 (Tolyl/Br)
1871.88 (H/Br)
1793.98 (H/H)
1603.69 (Tolyl/Br)
1435.69 (H/H)
1513.59 (H/Br)
(f)
3000
2000
Mass/Charge
(e)
Mass/Charge
2152.27 (H/H)
1800
1600
4000
Mass/Charge
2000
2000
2320.27 (Tolyl/Br)
1871.88 (H/Br)
1435.69 (H/H)
1793.98 (H/H)
1513.59 (H/Br)
1603.69 (Tolyl/Br)
(d)
3000
1800
1600
Mass/Charge
(c)
2000
1961.90 (Tolyl/Br)
1603.61 (Tolyl/Br)
1400
Mass/Charge
1961.98 (Tolyl/Br)
2000
1000
1871.83 (H/Br)
1513.54 (H/Br)
1155.25 (H/Br)
(b)
1245.32 (Tolyl/Br)
(a)
2200
Mass/Charge
FIGURE S1 MALDI-TOF mass spectra of products obtained by the polymerization of 2
in the presence of 5.5 equiv of Cy2NMe and 5.0 mol% of 10 at 50 oC in THF ([2]0 = 0.25
M) for 30 min (Conv. of 2 = 85%, Mn = 1620, Mw/Mn = 1.74); (a) whole spectrum, (b)
magnification between m/z = 1400-2400, 3 h (Conv. of 2 = 99%, Mn = 3270, Mw/Mn =
1.98); (c) whole spectrum, (d) magnification between m/z = 1400-2400, and 312 h (Conv.
6
of 2 = 100%, Mn = 4230, Mw/Mn = 1.99); (e) whole spectrum, (f) magnification between
m/z = 1400-2400.
●
● = H/I
○ = H/H
■ = unknow-1
◆ = unknow-2
◇ = unknow-3
●
●
○
◇
■
■
◇
○
◆
◆
FIGURE S2 MALDI-TOF mass spectra of products obtained by the polymerization of 1
in
the
presence
of
1.1
equiv
of
Cy2NMe
and
5.0
mol%
of
bis[tri(tert-butyl)phosphine]palladium in THF ([1]0 = 0.25 M) at 50 oC for 17 h (Mn = 4120,
Mw/Mn = 1.64).
7