Direct arylation polycondensation as simplified alternative for the synthesis of conjugated (co)polymers

doi:10.1016/j.progpolymsci.2013.04.006

Progress in Polymer Science

Volume 38, Issue 12, December 2013, Pages 1805-1814

https://doi.org/10.1016/j.progpolymsci.2013.04.006 Get rights and content

Abstract

Future application of conjugated (co)polymers, e.g. in electronic devices, requires the availability of up-scalable synthetic procedures. “Conventional” (hetero)aryl-(hetero)aryl coupling schemes often produce toxic or environmentally risky by-products. Here, so-called direct arylation schemes without use of organometallic reagents or related anion equivalents came in the focus of attention as simplified alternative to standard coupling procedures. Now, a couple of structurally defined conjugated (co)polymers can be generated in high yield and molecular weight via direct arylation polycondensation. The promising application potential of these materials as active component of organic solar cells has been demonstrated.

Introduction

Conventional (hetero)aryl-(hetero)aryl cross-coupling reactions for C single bond C bond formation after Suzuki [1], Stille [2], Negishi [3], or Kumada [4] are of highest relevance in organic and macromolecular chemistry. One disadvantage of these reactions is, however, the use of various organometallic reagents (or related anion equivalents) that produces stoichiometric amounts of by-products during coupling. These reagents and the resulting byproducts are, in addition, often toxic or environmentally risky, especially in the case of stannyl derivatives. Syntheses of these organometallic monomers often require multistep procedures as well as expensive purification steps. As example, purification of arylboronic acids/esters or aromatic trialkylstannyl derivatives is often challenging. In order to overcome these shortcomings new synthetic schemes, so-called direct arylation schemes without use of organometallic reagents came into the focus of attention and have been much improved during the last two decades [5]. One much-noticed application of (hetero)aryl-(hetero)aryl cross-coupling polycondensation is the generation of conjugated polymers for various potential applications in the field of organic electronics, e.g. as active components of organic light emitting diodes (OLEDs), organic field effect transistors (OFETs), and organic photovoltaic devices (OPV devices). Here, simplified and low-waste reaction schemes as direct arylation polycondensation represent an attractive alternative to the standard coupling procedures and may enable or facilitate up-scaling of promising materials to the industrial scale. The trend article will provide information on the state-of-the-art in the synthesis of conjugated (co)polymers by direct arylation polycondensation [6]. The results illustrate that high molecular weight and well-defined conjugated (co)polymers are now available via such direct arylation polycondensation schemes. First polymeric materials have been successfully tested as active components of organic solar cells.

Section snippets

Progress in direct arylation polycondensation

In 1999 Lemaire and co-workers [7] were the first who transferred direct arylation schemes for the aryl–aryl coupling of small molecules into polymer synthesis. They synthesized regioregular poly(3-alkylthiophene)s (P3AT, R = H, CH₃, (C₂H₄)CH(CH₃)(C₂H₅), C₈H₁₇) (P1–P4) by polycondensation of 2-iodo-3-alkylthiophenes in a Heck-type reaction using Pd(OAc)₂ as catalyst, equimolar amounts of nBu₄NBr and excess K₂CO₃ as base in DMF at 80 °C. In case of poly[3-(3-methyl-pentyl)thiophene] a yield of 89%

Conclusion

Direct arylation polycondensation schemes represent today, without any doubt, a novel and very promising synthetic alternative to “conventional” aryl–aryl couplings, also in the field of conjugated polymer synthesis. They combine high yields, low catalyst loadings and high molecular weights of the reaction products with an increased atom-economy (less reaction steps, no use of organometallic reagents or related anion equivalents as arylboronic esters/acids or stannyl derivatives). Nevertheless,

References (30)

A. Facchetti
π-Conjugated polymers for organic electronics and photovoltaic cell applications
Chem Mater
(2011)
T.J. Marks
Materials for organic and hybrid inorganic/organic electronics
MRS Bull
(2010)
N. Miyaura et al.
Palladium-catalyzed cross-coupling reactions of organoboron compounds
Chem Rev
(1995)
D.A. Schlüter
The tenth anniversary of Suzuki polycondensation (SPC)
J Polym Sci A Polym Chem
(2001)
J.K. Stille
The palladium-catalyzed cross-coupling reactions of organotin reagents with organic electrophiles
Angew Chem Int Ed
(1986)
B. Carsten et al.
Stille polycondensation for synthesis of functional materials
Chem Rev
(2011)
E. Negishi et al.
Selective carbon–carbon bond formation via transition metal catalysis. 3. A highly selective synthesis of unsymmetrical biaryls and diarylmethanes by the nickel- or palladium-catalyzed reaction of aryl- and benzylzinc derivatives with aryl halides
J Org Chem
(1977)
T.A. Chen et al.
Use of highly reactive zinc leads to a new, facile synthesis for polyarylenes
Macromolecules
(1993)
K. Tamao et al.
Selective carbon–carbon bond formation by cross-coupling of grignard reagents with organic halides. Catalysis by nickel–phosphine complexes
J Am Chem Soc
(1972)
R.S. Loewe et al.
Regioregular head-to-tail coupled poly(3-alkylthiophenes) made easy by the GRIM method: investigation of the reaction and the origin of regioselectivity
Macromolecules
(2001)
F. Požgan et al.
Ligand-free palladium-catalyzed direct arylation of heteroaromatics using low catalyst loadings
ChemSusChem
(2008)
J. Roger et al.
Ligand-less palladium-catalyzed direct 5-arylation of thiophenes at low catalyst loadings
Green Chem
(2009)
D.J. Schipper et al.
Direct arylation as a synthetic tool for the synthesis of thiophene-based organic electronic materials
Chem Mater
(2011)
Y. Tan et al.
Assessment of the intermediacy arylpalladium carboxylate complexes in the direct arylation of benzene: evidence for CH bond cleavage by “ligandless” species
J Am Chem Soc
(2011)
M. Baghbanzadeh et al.
Palladium-catalyzed direct arylation of heteroaromatic compounds: improved conditions utilizing controlled microwave heating
J Org Chem
(2011)
A. Facchetti et al.
Semiconducting polymers prepared by direct arylation polycondensation
Angew Chem Int Ed
(2012)
M. Sévignon et al.
New synthetic method for the polymerization of alkylthiophenes
Tetrahedron Lett
(1999)
Q. Wang et al.
Palladium-catalyzed dehydrohalogenative polycondensation of 2-bromo-3-hexylthiophene: an efficient approach to head-to-tail poly(3-hexylthiophene)
J Am Chem Soc
(2010)
Q. Wang et al.
Synthesis of end-capped regioregular poly(3-hexylthiophene)s via direct arylation
Macromol Rapid Commun
(2012)

W. Lu et al.

Polycondensation of dibromofluorene analogues with tetrafluorobenzene via direct arylation

Macromolecules

(2011)

Y. Fujinami et al.

Synthesis of thiophene- and bithiophene-based alternating copolymers via Pd-catalyzed direct CH arylation

ACS Macro Lett

(2012)

W. Lu et al.

Synthesis of π-conjugated polymers containing fluorinated arylene units via direct arylation: efficient synthetic method of materials for OLEDs

Macromolecules

(2012)

W. Lu et al.

Synthesis of 4,4′-dinonyl-2,2′-bithiazole-based copolymers via Pd-catalyzed direct CH arylation

Polym Chem

(2012)

P. Berrouard et al.

Synthesis of 5-alkyl[3,4-c]thienopyrrole-4,6-dione-based polymers by direct heteroarylation

Angew Chem Int Ed

(2012)

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Direct arylation polycondensation as simplified alternative for the synthesis of conjugated (co)polymers

Abstract

Introduction

Section snippets

Progress in direct arylation polycondensation

Conclusion

Chem Mater

MRS Bull

Palladium-catalyzed cross-coupling reactions of organoboron compounds

Chem Rev

The tenth anniversary of Suzuki polycondensation (SPC)

J Polym Sci A Polym Chem

The palladium-catalyzed cross-coupling reactions of organotin reagents with organic electrophiles

Angew Chem Int Ed

Stille polycondensation for synthesis of functional materials

Chem Rev

Selective carbon–carbon bond formation via transition metal catalysis. 3. A highly selective synthesis of unsymmetrical biaryls and diarylmethanes by the nickel- or palladium-catalyzed reaction of aryl- and benzylzinc derivatives with aryl halides

J Org Chem

Use of highly reactive zinc leads to a new, facile synthesis for polyarylenes

Macromolecules

Selective carbon–carbon bond formation by cross-coupling of grignard reagents with organic halides. Catalysis by nickel–phosphine complexes

J Am Chem Soc

Regioregular head-to-tail coupled poly(3-alkylthiophenes) made easy by the GRIM method: investigation of the reaction and the origin of regioselectivity

Macromolecules

Ligand-free palladium-catalyzed direct arylation of heteroaromatics using low catalyst loadings

ChemSusChem

Ligand-less palladium-catalyzed direct 5-arylation of thiophenes at low catalyst loadings

Green Chem

Direct arylation as a synthetic tool for the synthesis of thiophene-based organic electronic materials

Chem Mater

Assessment of the intermediacy arylpalladium carboxylate complexes in the direct arylation of benzene: evidence for CH bond cleavage by “ligandless” species

J Am Chem Soc

Palladium-catalyzed direct arylation of heteroaromatic compounds: improved conditions utilizing controlled microwave heating

J Org Chem

Semiconducting polymers prepared by direct arylation polycondensation

Angew Chem Int Ed

New synthetic method for the polymerization of alkylthiophenes

Tetrahedron Lett

Palladium-catalyzed dehydrohalogenative polycondensation of 2-bromo-3-hexylthiophene: an efficient approach to head-to-tail poly(3-hexylthiophene)

J Am Chem Soc

Synthesis of end-capped regioregular poly(3-hexylthiophene)s via direct arylation

Macromol Rapid Commun

Polycondensation of dibromofluorene analogues with tetrafluorobenzene via direct arylation

Macromolecules

Synthesis of thiophene- and bithiophene-based alternating copolymers via Pd-catalyzed direct CH arylation

ACS Macro Lett

Synthesis of π-conjugated polymers containing fluorinated arylene units via direct arylation: efficient synthetic method of materials for OLEDs

Macromolecules

Synthesis of 4,4′-dinonyl-2,2′-bithiazole-based copolymers via Pd-catalyzed direct CH arylation

Polym Chem

Synthesis of 5-alkyl[3,4-c]thienopyrrole-4,6-dione-based polymers by direct heteroarylation

Angew Chem Int Ed