Polymerization Kumada cross-coupling method

The first synthesis of HT rr-P3AT (Scheme 9.1), known as the McCullough method was reported in 1992 (Scheme 9.1, Table 9.1, entry 1) [25,26]. The key to this method is the regiospecific generation of 2-bromo-5-bromomagnesio-3-alkylthiophene 3 from 2-bromo-3-alkylthiophene, which is then polymerized by Kumada and coworkers [27-29] cross-coupling methods using catalytic amounts of... 

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