Polycondensation catalyst-transfer

FIGURE 3.26 Concept of the Kumada catalyst transfer polycondensation, dppp, propane-l,3-diylbis(diphenylphosphane) TM, transmetaUation RE, reductive elimination OA, oxidative addition. 

J. Wang, M. Ueda, T. Higashihara, Synthesis of All-Conjugated Donor-Acceptor-Donor ABA-Type Triblock Copolymers via Kumada Catalyst-Transfer Polycondensation. ACS Macro Lett. 2013,2,506-510. 

E. Kaul, V. Senkovskyy, R. Tkachov, V. Bocharova, H. Komber, M. Stamm, A. Kiriy, Synthesis of a Bifunctional Initiator for Controlled Kumada Catalyst- Transfer Polycondensation/Nitroxide-Mediated Polymerization and Preparation of Poly(3-Hexylthiophene)-Polystyrene Block Copolymer Therefrom. Macromolecules 2010,43,77-81. 

Scheme 22.10 Mechanism proposed for a catalyst transfer polycondensation using the Pd complex 28 as initiator and the SPC monomer 29. After C-C bond formation in 30, the Pd residue shifts over the r-part of...

Miyakoshi, R., A. Yokoyama, and T. Yokozawa. 2005. Catalyst-transfer polycondensation mechanism of Ni-catalyzed chain-growth polymerization leading to well-defined poly(3-hexylthiophene). JAm Chem Soc 127 (49) 17542-17547. 

Kaul et al. have reported on the syntheses of rod-coil P3HT-1 -PS with low polydispersity via a consecutive Kumada catalyst transfer polycondensation (KCTP) and... 

Chain-growth catalyst-transfer polycondensation (CTP) is a rapidly developing polymerization method, as it allows, in many cases, the above-mentioned limitations of step-growth polymerizations to be overcome. CTP provides a straightforward access to well-defined conjugated homopolymers (e.g., polythiophenes (1), polyfluorenes (2), polyphenylenes (3), etc.), alternate donor-acceptor copolymer e.g., 4) and all-conjugated block polymers (e.g., 5), Chart 20.1. 

Until recently, catalyst-transfer polycondensations were limited to the preparation of p-type 7i-conjugated polymers and block copolymers comprising relatively simple electron-rich building blocks (such as thiophene). On the other hand, well-defined conjugated donor-acceptor alternate copolymers and donor-acceptor all-conjugated block copolymers are needed for practical applications. Very recently, controlled polymerizations of a few electron-deficient monomers were also reported." ... 

One of the most highly researched conjugated polymers is poly(3-aIkylthiophene) (underivatized polythiophene is insoluble). In a synthetic method developed by McCullough [94, 96] and further modified by Yokozawa [95, 97], Kumada catalyst-transfer polycondensation (KCTP), also commonly known as Grignard metathesis polymerization... 

Miyakoshi R, Shimono K, Yokoyama A, Yokozawa T. Catalyst-transfer polycondensation for the synthesis of poly(p-phenylene) with controlled molecular weight and low polydispersity. J Am Chem Soc 2006 128 16012-16013. 

Yokoyama A, Kato A, Miyakoshi R, Yokozawa T. Precision synthesis of poly (n-hexylpyrrole) and its diblock copolymer with poly(p-phenylene) via catalyst-transfer polycondensation. Macromolecules 2008 41 7271-7273. 

Senkovskyy V, Tkachov R, Beryozkina T, Komber H, Oertel U, Horecha M, Bocharova V, Stamm M, Gevorgyan SA, Krebs FC, Kiriy A. Hairy poly(3-hexylthiophene) particles prepared via surface-initiated kumada catalyst-transfer polycondensation. J Am Chem Soc 2009 131 16445-16453. 

Bryan ZJ, McNeil AJ (2013) Conjugated polymer synthesis via catalyst-transfer polycondensation (CTP) mechanism, scope, and applications. Macromolecules 46 8395-8405... 

Beryozkina T, Senkovskyy V, Kaul E, Kiriy A (2008) Kumada catalyst-transfer polycondensation of thiophcaie-based oligomers robustness of a chain-growth mechanism. Macromolecules 41 7817-7823... 

Kiriy A, Senkovskyy V, Sommer M (2011) Kumada catalyst-transfer polycondensation mechanism, opportunities, and challenges. Macromol Rapid Commun 32 1503-1517... 

Tkachov R, Senkovskyy V, Komber H, Sommer J-U, Kiriy A (2010) Random catalyst walking along polymerized poly(3-hexylthiophene) chains in Kumada catalyst-transfer polycondensation. J Am Chem Soc 132 7803-7810... 

Sui A, Shi X, Wu S, Tian H, Geng Y, Wang F (2012) Controlled synthesis of polyfluorenes via Kumada catalyst transfer polycondensation with Ni(acac)2/dppp as the catalyst. Macromolecules 45 5436-5443... 

Doubina N, Ho A, Jen AKY, Luscombe CK (2009) Effect of initiators on the Kumada catalyst-transfer polycondensation reaction. Macromolecules 42 7670-7677... 

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