Synthesis of conjugated polymers via oxidative polymerization and related compositions
View Patent ↗An improved polymerization method including a method comprising providing a reaction mixture comprising a first monomer, an organic oxidant, and at least one Lewis acid or Brönsted acid, wherein the first monomer comprises at least one optionally substituted heterocyclic ring, wherein the heterocyclic ring comprises at least one heteroatom; and reacting the reaction mixture to obtain a conjugated polymer. The method can reduce the content of undesirable entities in the polymer such as halogens and metals, which can be useful in organic electronic device applications. Purification methods also are adapted to remove organic and inorganic impurities.
1. A method comprising:
polymerizing by oxidative chemical polymerization at least one first monomer in the presence of at least one organic oxidant, wherein the first monomer comprises at least one optionally substituted heterocyclic ring, wherein the heterocyclic ring comprises at least one heteroatom, wherein the polymerizing is carried out with a separate Lewis acid also present.
2. The method of claim 1 , wherein the first monomer consists of one optionally substituted heterocyclic ring.
3. The method of claim 1 , wherein the first monomer comprises at least two optionally substituted heterocyclic rings.
4. The method of claim 1 , wherein the first monomer comprises at least two optionally substituted fused heterocyclic rings.
5. The method of claim 1 , wherein the heteroatom is O, S, or N.
6. The method of claim 1 , wherein the first monomer is represented by:
wherein R, R 1 , R 2 , and R 3 are each a hydrogen or an optionally substituted linear, branched or cyclic alkyl, aryl, alkoxy, aryloxy, alkylthio, arylthio, acyl, ether, or polyether.
7. The method of claim 1 , wherein the first monomer is represented by:
wherein R, R 1 , R 2 , and R 3 are each independently a linear or branched alkyl, alkoxy, ether or polyether, or together a cyclic alkyl, alkoxy, ether or polyether.
8. The method of claim 1 , wherein the first monomer is a substituted thiophene.
9. The method of claim 1 , wherein the first monomer is a 3-substituted thiophene.
10. The method of claim 1 , wherein the first monomer is a 3,4-substituted thiophene.
11. The method of claim 1 , wherein the first monomer is a dimer comprising a first optionally substituted thiophene unit and a second optionally substituted thiophene unit.
12. The method of claim 1 , wherein the first monomer is free of any halogen substituents.
13. The method of claim 1 , wherein the first monomer is free of any polymerizable halogen group directly bonded to the heterocyclic ring.
14. The method of claim 1 , wherein the first monomer comprises at least one polyether substituent.
15. The method of claim 1 , wherein the first monomer comprises at least one alkoxy substituent.
16. The method of claim 1 , wherein the organic oxidant comprises an optionally substituted quinone group.
17. The method of claim 1 , wherein the organic oxidant comprises an optionally substituted quinonimine group or an optionally substituted quinondiimine group.
18. The method of claim 1 , wherein the organic oxidant comprises an optionally substituted nitroarene group.
19. The method of claim 1 , wherein the organic oxidant is represented by formula (I), (II), or (III):
wherein X 1 and X 2 are each independently O or N—R 6 ′, and wherein R 1 ′, R 2 ′, R 3 ′, R 4 ′, R 5 ′ and R 6 ′ are each independently a hydrogen, a halogen, or an optionally substituted linear, branched, or cyclic alkyl, alkenyl, alkynyl, alkoxy, alkylthio, ester, ketone, carboxylic acid, carboxylate ester, nitro, sulfonic acid, sulfonate ester, sulfonic acid amide, or cyano group.
20. The method of claim 1 , wherein the organic oxidant is 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ).
21. The method of claim 1 , wherein the Lewis acid comprises BF 3 .
22. The method of claim 1 , wherein the polymerizing is carried out in the presence of at least one solvent.
23. The method of claim 1 , wherein the polymerizing is carried out substantially in absence of any solvent.
24. The method of claim 1 , wherein the polymerizing step is carried out in a reaction mixture, wherein the reaction mixture further comprises a second monomer different from the first monomer.
25. The method of claim 1 , wherein the polymerizing step is carried out in a reaction mixture, wherein the reaction mixture further comprises a second monomer different from the first monomer, wherein the first monomer is 3,4-disubstituted thiophene, and wherein the second monomer is 3-substituted thiophene.
26. The method of claim 1 , further comprising quenching the reaction with an organometallic quenching agent, a metal quenching agent, or an organic quenching agent.
27. The method of claim 1 , further comprising quenching the reaction with at least one metallocene.
28. The method of claim 1 , further comprising quenching the reaction with zinc.
29. The method of claim 1 , wherein the polymerizing step produces a conjugated polymer, the method further comprising dedoping the conjugated polymer with at least one reducing agent.
30. The method of claim 1 , wherein the polymerizing step produces a conjugated polymer, the method further comprising dedoping the conjugated polymer with hydrazine.
31. The method of claim 1 , wherein the polymerizing is carried out substantially free of any metal-based oxidant or metal-based catalyst.
32. The method of claim 1 , wherein the polymerization is carried out without a Brönsted acid.
33. The method of claim 1 , wherein the polymerization is carried out substantially in absence of any proton source.
34. The method of claim 1 , wherein the first monomer does not comprise a halogen bonded to the heterocyclic ring, and wherein polymerization is carried out without a metal oxidant, initiator, or catalyst.
35. The method of claim 34 , wherein the polymerizing step produces a polymer having an Mn of at least 1,000 g/mol.
36. The method of claim 1 , wherein the Lewis acid comprises at least one BF 3 etherate.
37. The method of claim 36 , wherein the BF 3 etherate is BF 3 .(C 2 H 5 ) 2 O.
38. The method of claim 1 , wherein the polymerizing step produces a polymer, and after polymerization, the polymer is not subjected to a dedoping step.
39. The method of claim 1 , wherein the polymerizing is carried out and the resulting polymer is not subjected to a dedoping step.
40. The method of claim 1 , wherein the first monomer comprises at least three optionally substituted heterocyclic rings.
41. The method of claim 1 , wherein the heterocyclic ring is a five-member ring comprising at least one heteroatom, and the heteroatom is S or N.
42. The method of claim 1 , wherein the first monomer comprises at least one fluorinated substituent.