146.21, 132.78, 126.20, 122.21, 115.50, 106.29, 46.59, 38.81,
31.89, 31.78, 31.44, 30.11, 29.78, 29.52, 29.30, 26.47, 26.45, 22.66,
22.63, 14.11, 14.08. MALDI-TOF-MS: m/z 872.46 (50%), 873.46
(25), 874.46 (100), 875.46 (55), 876.46 (60), 877.46 (60), 877.46
(25), 878.47 (5).
FTF
The same procedure was employed as for FPF, but using 3,6-
bis (5-bromofuran-2-yl)-2,5-dihydro-2,5-bis(2-hexyldecyl)pyrro
lo[3,4-c]pyrrolo-1,4-dione (1) (105 mg, 120 mmol) and 2,20-(2,5-
thiophenediyl)bis[4,4,5,5-tetramethyl-1,3,2-dioxaborolane] (4)
(40 mg, 119 mmol). FTF was obtained as a dark blue powder, 44
mg (46%). 1H NMR: 9.0 (br, 2H), 7.5 (br, 4H), 7.1 (br, 2H), 4.0
(br, 4H), 1.89 (br, 2H), 1.20–1.00 (br, 48H), 0.80–0.70 (br, 12H).
GPC: Mn ¼ 15 000 g molꢀ1, PDI ¼ 3.5.
FPF
To an argon bubbled solution of 3,6-bis(5-bromofuran-2-yl)-2,5-
dihydro-2,5-bis(2-hexyldecyl)pyrrolo[3,4-c]pyrrolo-1,4-dione (1)
(112 mg, 128 mmol), 2,20-(1,4-phenylene)bis[4,4,5,5-tetramethyl-
1,3,2-dioxaborolane] (5) (42 mg, 127 mmol), a 50% Aliquat solu-
tion in toluene (0.3 ml), triphenylphosphine (4.1 mg, 15 mmol),
K3PO4 (60 mg, 0.28 mmol) in toluene (3.5 ml) with demineralised
water (0.4 ml), and tris(dibenzylideneacetone)dipalladium(0) (7.0
mg, ꢁ7.6 mmol) was added. This mixture was stirred for 3 days at
115 C after which the crude polymer was precipitated in meth-
TFT
The same procedure was employed as for FPF, but using 3,6-
bis (5-bromothien-2-yl)-2,5-dihydro-2,5-bis(2-hexyldecyl)pyrro
lo[3,4-c]pyrrolo-1,4-dione (2) (108 mg, 119 mmol) and 2,20-(2,5-
furandiyl)bis[4,4,5,5-tetramethyl-1,3,2-dioxaborolane] (3) (39
mg, 120 mmol). TFT was obtained as a dark blue powder, 56 mg
(58%). 1H NMR: 8.9 (br, 2H), 7.1 (br, 2H), 6.9 (br, 2H), 4.1 (br,
4H), 1.9 (br, 2H), 1.2–1.0 (br, 48H), 0.8–0.7 (br, 12H). GPC:
Mn ¼ 16 000 g molꢀ1, PDI ¼ 2.6.
€
anol. The solids were filtered over a Buchner funnel and re-dis-
solved in chloroform (80 ml) and stirred under reflux with 28%
aqueous ammonium hydroxide (80 ml) solution for 3 h. The layers
were separated and the organic phase was stirred with ethylene-
diaminetetraacetate (300 mg) for 3 h. Then demineralised water
(100 ml) was added, and the mixture was stirred for another hour.
The layers were separated and the organic layer was washed with
demineralised water and reduced in volume in vacuum and
precipitated in methanol. The precipitate was collected in
a Soxhlet thimble and was extracted with methanol, hexane and
chloroform until the extracts were colourless. The chloroform
fraction was reduced in volume and precipitated in methanol and
filtered over a 4.5 mm PTFE filter. The polymer was collected and
Results and discussion
Synthesis
In the remainder of the PDPP-XYX notation will be abbreviated
as XYX, with X ¼ F or T and Y ¼ F, T, or P (Scheme 1). The
synthesis of the new XYX polymers was accomplished via
a Suzuki polymerization as outlined in Scheme 2. This procedure
required access to 3,6-bis(5-bromofuran-2-yl)-2,5-dihydro-2,5-
bis(2-hexyldecyl)pyrrolo[3,4-c]pyrrolo-1,4-dione (1) and 3,6-
bis (5-bromothien-2-yl)-2,5-dihydro-2,5-bis(2-hexyldecyl)pyrrol
o[3,4-c]pyrrolo-1,4-dione (2) as well as 2,20-(2,5-fur-
andiyl)bis[4,4,5,5-tetramethyl-1,3,2-dioxaborolane] (3), 2,20-(2,5-
thiophenediyl)bis[4,4,5,5-tetramethyl-1,3,2-dioxaborolane] (4),
and 2,20-(1,4-phenylene)bis[4,4,5,5-tetramethyl-1,3,2-dioxabor-
olane] (5).
ꢁ
dried in a vacuum oven at 60 C overnight, resulting in 70 mg
(69%) of a dark blue powder. 1H NMR: 8.6 (br, 2H), 7.4 (br, 4H),
7.1 (br, 2H), 4.0 (br, 4H), 1.9 (br, 2H), 1.20–1.00 (br, 48H), 0.8–0.7
(br, 12H). GPC: Mn ¼ 17 000 g molꢀ1, PDI ¼ 5.5.
The synthesis of monomer 1 is depicted in Scheme 3. In the
first step 2-furonitrile and diethyl succinate were condensed to
form 6 in a one pot reaction. DPP derivative 6 was then alkylated
using potassium carbonate as the base yielding the better soluble
DPP derivative 7. Subsequent bromination yielded the desired
monomer 1. The other monomers were synthesized as described
before (2)13 or were commercially available (3–5).
FFF
The same procedure was employed as for FPF, but using 3,6-
bis (5-bromofuran-2-yl)-2,5-dihydro-2,5-bis(2-hexyldecyl)pyrro
lo[3,4-c]pyrrolo-1,4-dione (1) (141 mg, 161 mmol) and 2,20-(2,5-
furandiyl)bis[4,4,5,5-tetramethyl-1,3,2-dioxaborolane] (3) (52
mg, 162 mmol). FFF was obtained as a dark blue powder, 55 mg
(44%). 1H NMR: 8.5 (br, 2H), 6.8 (br, 4H), 6.7 (br, 2H), 4.1 (br,
2H), 3.8 (br, 2H), 1.9 (br, 2H), 1.20–1.00 (br, 48H), 0.80–0.70 (br,
12H). GPC: Mn ¼ 13 000 g molꢀ1, PDI ¼ 2.8.
The polymers were obtained via Suzuki polymerization in
yields varying from 44% to 69% after purification by Soxhlet
extraction. Only the chloroform fraction was used and the
Scheme 2 Synthesis of the polymers described in this study: (i) Pd2(dba)3, K3PO4, PPh3, Aliquat 336, water, toluene, yield 44–69%.
1602 | J. Mater. Chem., 2011, 21, 1600–1606 This journal is ª The Royal Society of Chemistry 2011