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Guo ZS, et al. Sci China Chem April (2011) Vol.54 No.4
precipitate. The precipitate was dissolved in chloroform and
reprecipitated from methanol. The resulting precipitate was
placed in a Soxhlet apparatus and extracted with refluxed
acetone for 48 h to remove small molecules and catalyst
residue, and then was dried at 60 °C in a vacuum oven to
1
give P1 as a light yellow solid (675 mg, 86%). H NMR
(300 MHz, CDCl3, ppm): = 7.68–7.86 (m, 8H), 2.11–2.12
(m, 4H), 0.88–1.26 (m, 17H), 0.77–0.87 (m, 10H). 13C
NMR (50 MHz, CDCl3, ppm): = 152.0, 140.8, 140.2,
132.3, 129.0, 128.8, 128.6, 127.4, 126.4, 121.8, 120.2, 55.6,
40.6, 31.7, 29.9, 29.2, 24.1, 22.8, 21.8, 14.2. FT-IR (KBr):
2926, 2853, 1636, 1457, 1250, 1117, 885, 813 cm1.
PFH-PO-20-1 (P2)
This polymer was prepared following the similar procedures
used to prepare polymer P1 as a light yellow solid (674 mg,
83%). 1H NMR (300 MHz, CDCl3, ppm): = 7.68–7.86 (m,
8H), 1.76–2.12 (m, 5H), 1.15–1.26 (m, 18H), 0.80–0.88 (m,
10H). 13C NMR (50 MHz, CDCl3, ppm): = 152.0, 140.8,
140.2, 132.5, 132.3, 129.0, 128.8, 128.6, 127.4, 126.4,
121.8, 120.2, 55.6, 40.6, 32.0, 31.6, 31.0, 29.9, 29.2, 27.2,
25.9, 24.1, 22.8, 21.6, 14.2. FT-IR (KBr): 2925, 2851, 1633,
1457, 1249, 884, 813 cm1.
PFH-PO-10-1 (P3)
This polymer was prepared following the similar procedures
used to prepare polymer P1 as a light yellow solid (733 mg,
85%). 1H NMR (300 MHz, CDCl3, ppm): = 7.68–7.86 (m,
8H), 2.11–2.13 (m, 4H), 1.26–1.52 (m, 20H), 0.77–0.88 (m,
11H). 13C NMR (50 MHz, CDCl3, ppm): = 152.0, 151.7,
140.8, 140.2, 132.5, 132.3, 129.0, 128.8, 128.5, 127.4,
126.4, 121.8, 120.2, 55.5, 40.6, 32.0, 31.7, 31.4, 31.1, 29.9,
29.6, 29.2, 27.8, 26.5, 24.1, 22.8, 21.7, 14.2. FT-IR (KBr):
2924, 2851, 1637, 1457, 1249, 998, 884, 813 cm1.
Scheme 1 The synthetic route to these polymers.
bis(6-dioctylphosphine oxide hexyl)-9H-fluorene (4) with a
72% yield. 2,7-Dibromo-9,9-dihexylfluorene (5) reacted
with 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi(1,3,2-dioxaborolane)
to afford 2,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-
9,9-dihexylfluorene (6) with a 75% yield.
PFH-PO-1-1 (P4)
This polymer was prepared following the similar procedures
used to prepare polymer P1 as a light yellow solid (778 mg,
Monomers 4 and 5 with different ratios were polymerized
with monomer 6 via a palladium-mediated Suzuki cross-
coupling reaction to afford four corresponding phosphonic-
functionalized polymers P1, P2, P3, and P4, respectively,
as shown in Scheme 1. The crude polymers were washed
with methanol, water, and methanol again, successively,
and were placed in a Soxhlet apparatus and extracted with
refluxed acetone for 48 h, and then were dried at 60 °C in a
vacuum oven. These polymers were readily soluble in
common organic solvents, such as THF, CHCl3, and toluene.
Therefore, their basic chemical structures were clearly de-
1
64%). H NMR (300 MHz, CDCl3, ppm): 7.67–7.87 (m,
16H), 2.13 (m, 8H), 0.78–1.56 (m, 128H). 13C NMR (50
MHz, CDCl3, ppm): 152.0, 151.6, 140.7, 140.5, 140.2,
126.4, 121.5, 120.2, 55.6, 55.4, 40.5, 31.9, 31.6, 31.4, 31.1,
29.8, 29.6, 29.2, 26.9, 24.0, 22.8, 21.8, 14.2. FT-IR (KBr):
2925, 2852, 1636, 1452, 1147, 813 cm1.
3 Results and discussion
3.1 Synthesis of polymers P1–P4 and characterization
1
termined by H and 13C NMR, and FT-IR. The FT-IR fea-
Scheme 1 illustrates a synthetic approach to monomers 4
and 6. The reaction of di-n-butylphosphite (1) with C8H17MgBr
afforded dioctylphosphine oxide (2) with a 69% yield,
which was followed by the SN2 reaction with 2,7-dibromo-9,9-
bis(6-bromohexyl)-9H-fluorene (3) to give 2,7-dibromo-9,9-
ture with characteristics of 1633–1637 cm1 was proved the
existence of P=O groups in these polymers. The molecular
weights of these polymers were determined by gel permea-
tion chromatography (GPC) with THF as the eluent, cali-
brated against polystyrene standards. As shown in Table 1,