Development of a New Dehydrogenative Method for the Synthesis of Polydioxythiophenes

ABSTRACT

Conjugated polymers have proven to be capable and polyvalent materials for organic electronic applications. However, mainstream adoption has been hampered due to synthetic constraints such as the number of synthetic steps as well as the cost or toxicity of the critical C─C coupling step using Suzuki–Miyaura or Migita–Stille methods. This problem has been partially addressed with the development of direct (hetero)arylation polymerization (DHAP), which allows for polymerization through the coupling of a C─X and a C─H bond and thereby avoids several functionalization steps required by other methods. Yet, this process could be further simplified and rendered more benign through the coupling of two C─H bonds using molecular oxygen as an oxidant to accomplish polymerization. In this paper, we explore such a method, called Oxi‐DArP, to obtain polythiophene derivatives using a PEPPSI‐ i Pr palladium catalyst as well as molecular oxygen as the sole oxidant. This method allowed us to obtain in situ doped SEDOT polymers with M _n values of up to 18 kDa and conductivity values up to 14 S/cm.