Semiconducting materials based on naphthalenediimide-vinylene-oligothiophene-vinylene polymers

Abstract

The present invention provides a polymer comprising a unit of formula, ##STR00001##
wherein R.sup.1 and R.sup.2 are independently from each other C.sub.1-30-alkyl, C.sub.2-30-alkenyl, C.sub.2-30-alkynyl, phenyl or a 5 to 8 membered heterocyclic ring system, wherein each of the C.sub.1-30-alkyl, C.sub.2-30-alkenyl or C.sub.2-30-alkynyl group may be substituted with 1 to 10 substituents independently selected from the group consisting of halogen, CN, NO.sub.2, OH, NH.sub.2, NH(C.sub.1-20-alkyl), N(C.sub.1-20-alkyl).sub.2, NHC(O)(C.sub.1-20-alkyl), S(O).sub.2OH, CHO, C(O)C.sub.1-20-alkyl, C(O)OH, C(O)OC.sub.1-20-alkyl, C(O)NH.sub.2, CO(O)NHC.sub.1-20-alkyl, C(O)N(C.sub.1-20-alkyl).sub.2, OC.sub.1-20-alkyl, OC(O)C.sub.1-20-alkyl, SiH.sub.3, SiH.sub.2(C.sub.1-20-alkyl), SiH(C.sub.1-20-alkyl).sub.2, Si(C.sub.1-20-alkyl).sub.3, C.sub.4-8-cycloalkyl, phenyl and a 5 to 8 membered heterocyclic ring system, and phenyl and the 5 to 8 membered heterocyclic ring system may be substituted with 1 to 5 C.sub.1-16-alkyl groups, is 1, 2 or 3 and n is an integer from 2 to 10'000, a process for the preparation of the polymer and an electronic device comprising the polymer.

Claims

1. A polymer comprising a unit of formula ##STR00020## wherein R.sup.1 and R.sup.2 are independently from each other C.sub.1-30-alkyl, C.sub.2-30-alkenyl, C.sub.2-30-alkynyl, phenyl or a 5 to 8 membered heterocyclic ring system, wherein each of the C.sub.1-30-alkyl, C.sub.2-30-alkenyl or C.sub.2-30-alkynyl group may be substituted with 1 to 10 substituents independently selected from the group consisting of halogen, CN, NO.sub.2, OH, NH.sub.2, NH(C.sub.1-20-alkyl), N(C.sub.1-20-alkyl).sub.2, NHC(O)(C.sub.1-20-alkyl), S(O).sub.2OH, CHO, C(O)C.sub.1-20-alkyl, C(O)OH, C(O)OC.sub.1-20-alkyl, C(O)NH.sub.2, CO(O)NHC.sub.1-20-alkyl, C(O)N(C.sub.1-20-alkyl).sub.2, OC.sub.1-20-alkyl, OC(O)C.sub.1-20-alkyl, SiH.sub.3, SiH.sub.2(C.sub.1-20-alkyl), SiH(C.sub.1-20-alkyl).sub.2, Si(C.sub.1-20-alkyl).sub.3, C.sub.4-8-cycloalkyl, phenyl and a 5 to 8 membered heterocyclic ring system, and phenyl or a 5 to 8 membered heterocyclic ring system may be substituted with 1 to 5 C.sub.1-16-alkyl groups, o is 2 or 3 and n is an integer from 2 to 10,000.

2. The polymer of claim 1, wherein R.sup.1 and R.sup.2 are independently from each other C.sub.6-30-alkyl, C.sub.6-30-alkenyl, C.sub.6-30-alkynyl, or phenyl, wherein each of the C.sub.6-30-alkyl, C.sub.6-30-alkenyl or C.sub.6-30-alkynyl groups may be substituted with 1 to 10 substituents independently selected from the group consisting of halogen, CN, NO.sub.2, OH, NH.sub.2, NH(C.sub.1-20-alkyl), N(C.sub.1-20-alkyl).sub.2, NHC(O)(C.sub.1-20-alkyl), S(O).sub.2OH, CHO, C(O)C.sub.1-20-alkyl, C(O)OH, C(O)OC.sub.1-20-alkyl, C(O)NH.sub.2, CO(O)NHC.sub.1-20-alkyl, C(O)N(C.sub.1-20-alkyl).sub.2, OC.sub.1-20-alkyl, and NOC(O)C.sub.1-20-alkyl, and phenyl may be substituted with 1 or 2 C.sub.1-16-alkyl groups.

3. The polymer of claim 1, wherein R.sup.1 and R.sup.2 are independently from each other C.sub.6-30-alkyl, C.sub.6-30-alkenyl or C.sub.6-30-alkynyl, wherein each of the C.sub.6-30-alkyl, C.sub.6-30-alkenyl or C.sub.6-30-alkynyl group may be substituted with 1 to 10 substituents independently selected from the group consisting of halogen, CN, NO.sub.2, NH(C.sub.1-20-alkyl), N(C.sub.1-20-alkyl).sub.2, NHC(O)(C.sub.1-20-alkyl), C(O)C.sub.1-20-alkyl, C(O)OC.sub.1-20-alkyl, C(O)NH.sub.2, CO(O)NHC.sub.1-20-alkyl, C(O)N(C.sub.1-20-alkyl).sub.2, OC.sub.1-20-alkyl, and NOC(O)C.sub.1-20-alkyl.

4. The polymer of claim 1, wherein R.sup.1 and R.sup.2 are independently from each other C.sub.6-30-alkyl, wherein each of the C.sub.6-30-alkyl may be substituted with 1 to 10 substituents independently selected from the group consisting of halogen, CN, NO.sub.2, NH(C.sub.1-20-alkyl), N(C.sub.1-20-alkyl).sub.2, NHC(O)(C.sub.1-20-alkyl), C(O)C.sub.1-20-alkyl, C(O)OC.sub.1-20-alkyl, C(O)NH.sub.2, CO(O)NHC.sub.1-20-alkyl, C(O)N(C.sub.1-20-alkyl).sub.2, OC.sub.1-20-alkyl, and NOC(O)C.sub.1-20-alkyl.

5. The polymer of claim 1, wherein R.sup.1 and R.sup.2 are independently from each other C.sub.10-30-alkyl.

6. The polymer of claim 5, wherein R.sup.1 and/or R.sup.2 are independently from each other 2-octyldodecyl.

7. The polymer of claim 1, wherein o is 2.

8. The polymer of claim 1, wherein n is an integer from 5 to 1,000.

9. The polymer of claim 1, wherein n is an integer from 5 to 500.

10. The polymer of claim 1, wherein n is an integer from 10 to 100.

11. The polymer of claim 1 comprising a unit of formula ##STR00021## wherein n is an integer from 20 to 100.

12. An electronic device comprising the polymer of claim 1 as semiconducting material.

13. The electronic device of claim 12, wherein the electronic device is an organic field effect transistor.

14. The electronic device of claim 12, wherein the electronic device is an organic photovoltaic device.

15. A semiconducting material comprising the polymer of claim 1.

16. A process for the preparation of the polymer of claim 1, comprising reacting a compound of formula ##STR00022## wherein R.sup.1 and R.sup.2 are independently from each other C.sub.1-30-alkyl, C.sub.2-30-alkenyl, C.sub.2-30-alkynyl, phenyl or a 5 to 8 membered heterocyclic ring system, wherein each of the C.sub.1-30-alkyl, C.sub.2-30-alkenyl or C.sub.2-30-alkynyl group may be substituted with 1 to 10 substituents independently selected from the group consisting of halogen, CN, NO.sub.2, OH, NH.sub.2, NH(C.sub.1-20-alkyl), N(C.sub.1-20-alkyl).sub.2, NHC(O)(C.sub.1-20-alkyl), S(O).sub.2OH, CHO, C(O)C.sub.1-20-alkyl, C(O)OH, C(O)OC.sub.1-20-alkyl, C(O)NH.sub.2, CO(O)NHC.sub.1-20-alkyl, C(O)N(C.sub.1-20-alkyl).sub.2, OC.sub.1-20-alkyl, OC(O)C.sub.1-20-alkyl, SiH.sub.3, SiH.sub.2(C.sub.1-20-alkyl), SiH(C.sub.1-20-alkyl), Si(C.sub.1-20-alkyl).sub.3, C.sub.4-8-cycloalkyl, phenyl and a 5 to 8 membered heterocyclic ring system, and phenyl and the 5 to 8 membered heterocyclic ring system may be substituted with 1 to 5 C.sub.1-16-alkyl groups, and X is triflate or halogen, with a compound of formula ##STR00023## wherein R.sup.3 and R.sup.4 are independently from each other H or C.sub.1-10-alkyl, or R.sup.3 and R.sup.4 together with the OBO unit linking them form a cycle which may be substituted with one or two C1-6-alkyl, M is an alkali metal, an alkaline earth metal or Al, m is 1, 2 or 3, o is 2 or 3.

17. The process of claim 16, wherein X is Br.

18. The process of claim 16, wherein R.sup.3 and R.sup.4 together with the OBO unit linking them form a five-membered cycle.

19. The process of claim 16, wherein R.sup.3 and R.sup.4 together with the OBO unit linking them form a five-membered cycle, which is substituted with one or two C1-6-alkyl.

20. The process of claim 19, wherein the five-membered cycle is substituted with one or two methyl.

Description

EXAMPLES

Example 1

Preparation of Polymer 1a

(1) ##STR00018##

Preparation of Compound 3a

(2) A mixture of 5,5-diethynyl-2,2-bithiophene (4a) (2.2 g, 10 mmol), pinacolborane (6a) (2.7 g, 21 mmol) and ZrCp.sub.2HCl (Schwartz's reagent) (260 mg, 1 mmol) is sealed in a tube and stirred at 65 C. for 48 hours. Afterwards, the mixture is passed through silica gel pad and further purified on reverse phase column using hexane and ethyl acetate as eluent (hexane:ethyl acetate=10:1) to yield compound 3a as a white solid (2.1 g, 49%). .sup.1H NMR (400 MHz, CDCl.sub.3) 7.39 (d, 2H, J=18 Hz), 7.07 (d, 2H, J=3.6 Hz), 7.97 (d, 2H, J=3.6 Hz), 5.97 (d, 2H, J=18 Hz), 1.50 (s, 24H).

Preparation of Polymer 1a

(3) Compound 2a (300 mg, 0.31 mmol), compound 3a (180 mg, 0.38 mmol), N-phenylpyrrole-P(tert-butyl).sub.2 (18 mg, 0.06 mmol), Pd(OAc).sub.2 (3 mg, 0.02 mmol) and LiOH (96 mg, 2.29 mmol) are added to a Schlenk tube. The reaction vessel is evacuated and refilled with N.sub.2 3 times. Anhydrous THF (13 mL) is then added and heated under N.sub.2 at 70 C. After 20 minutes, 1 drop of 2-bromothiophene is added and allowed to stir for 1 h. 1 drop of 2-thiophene boronic acid is added and the reaction mixture is allowed to stir at 70 C. for another 1 hour. The reaction mixture is precipitated in a large beaker of stirring MeOH (900 mL) for 1 hour before being filtered and the residue is subjected to Soxhlet extraction with acetone (250 mL) overnight until the extract is colorless. The residue is dried under vacuum, dissolved in minimum amount of hot chlorobenzene and precipitated in a beaker of stirring MeOH (900 mL) for 1 hour before being filtered and the residue is dried under vacuum overnight to yield polymer 1a (310 mg, 97%). .sup.1H NMR (400 MHz, DCE, r.t.) 9.06 (brs, 2H), 8.74 (d, 2H, 15.6 Hz), 7.64 (d, 2H, 15.6 Hz), 7.27-7.03 (m, 4H), 4.25 (br, 4H), 2.40 (br, 2H), 1.49-1.17 (m, 64H), 1.01-0.90 (brs, 12H). Mn: 3.4410.sup.4, PDI: 2.06.

Example 2

Preparation of Polymer 1b

(4) ##STR00019##

Preparation of Compound 3b

(5) A mixture of 2,5-diethynylthiophene (4b) (1.4 g, 10 mmol), pinacolborane (6a) (2.8 g, 21 mmol) and ZrCp.sub.2HCl (Schwartz's reagent) (260 mg, 1 mmol) is sealed in a tube and stirred at 65 C. for 70 hours. Afterwards, the mixture is passed through silica gel pad and further purified on reverse phase column using hexane and ethyl acetate as eluent (hexane:ethyl acetate=15:1) to yield compound 3b as a white solid (1.55 g, 40%). .sup.1H NMR (400 MHz, CDCl.sub.3) 7.38 (d, 2H, J=18 Hz), 6.95 (s, 2H), 5.91 (d, 2H, J=18 Hz), 1.50 (s, 24H).

Preparation of Polymer 1b

(6) Compound 2a (450 mg, 0.46 mmol), compound 3b (177 mg, 0.46 mmol), N-phenylpyrrole-P(tert-butyl).sub.2 (21 mg, 0.07 mmol), Pd(OAc).sub.2 (4 mg, 0.02 mmol) and LiOH (115 mg, 2.74 mmol) are added to a Schlenk tube. The reaction vessel is evacuated and refilled with N.sub.2 3 times. Anhydrous THF (11 mL) is then added and heated under N.sub.2 at 70 C. After 22 hours, 1 drop of 2-bromothiophene is added and allowed to stir for 1 hour. 1 drop of 2-thiophene boronic acid is added and the reaction mixture is allowed to stir at 70 C. for another 4 hours. The reaction mixture is precipitate in a large beaker of stirring MeOH (900 mL) for 1 hour before being filtered and the residue is subjected to Soxhlet extraction with acetone (250 mL) overnight until the extract is colorless. The residue is dried under vacuum, dissolved in minimum amount of hot chlorobenzene and precipitated in a beaker of stirring MeOH (900 mL) for 1 hour before being filtered and the residue is dried under vacuum overnight to yield polymer 1b. (330 mg, 73%). .sup.1H NMR (400 MHz, DCE, r.t) 9.06 (brs, 2H), 8.70 (d, 2H, 15.6 Hz), 7.58 (d, 2H, 15.6 Hz), 7.52-7.40 (m, 2H), 4.29 (br, 4H), 2.14 (br, 2H), 1.50-1.34 (m, 64H), 1.01-0.90 (brs, 12H). Mn: 2.8510.sup.4, PDI: 2.25.

Example 3

Preparation of a Top-Gate Bottom-Contact Field-Effect Transistors Comprising the Polymer 1a, Respectively, 1b as Semiconducting Material

(7) The polymer 1a is dissolved in toluene (5 mg/ml) and spin coated on a PET substrate with litographically patterned silver (Ag) contact (W/L=1000, L=10 m) at 1500 rpm for 1 minute followed by drying on a 110 C. hotplate for 2 minute.

(8) The polymer 1b is dissolved in tetralin (5 mg/ml) and spin coated (heated solution and substrate at 110 C.) on a PET substrate with litographically patterned silver (Ag) contact (W/L=1000, L=10 m) at 1000 rpm for 2 minute followed by drying on a 110 C. hotplate for 2 minute.

(9) In both cases, polystyrene is used as gate dielectric (4 wt % in isopropyl actetate) and is deposited by spin coating at 3600 rpm for 30 sec followed by drying on a 90 C. hotplate for 30 sec. All the depositions are done in ambient atmosphere. Finally gold (Au) is deposited by thermal evaporation for use as gate electrode. The thickness of the semiconducting layer is 30 nm, and the thickness of the dielectric layer is 420 nm.

(10) Average charge carrier mobility of the transistor comprising the polymer 1a is 0.03 cm.sup.2Ns with on/off ratio of 10.sup.5, while the charge carrier mobility of the transistor comprising the polymer of formula 1b is 0.04 cm.sup.2Ns with on/off 10.sup.4.