Siloxane-Based Hybrid Semiconducting Polymers Prepared by Fluoride-Mediated Suzuki Polymerization

Abstract

Siloxane-containing materials are a large and important class of organic-inorganic hybrids. In this report, a practical variation of the Suzuki polymerization to generate semiconducting polymeric hybrids based on siloxane units, which proceeds under essentially nonbasic conditions, is presented. This method generates solution-processable poly(diketopyrrolopyrrole-alt-benzothiadiazole) (PDPPBT-Si) consisting of the hybrid siloxane substituents, which could not be made using conventional methods. PDPPBT-Si exhibits excellent ambipolar transistor performance with well-balanced hole and electron FET mobilities. The siloxane-containing DPP-thiophene polymer classes (PDPP3T-Si and PDPP4T-Si), synthesized by this method, exhibit high hole mobility of up to 1.29 cm2V-1s-1. This synthetic approach should provide access to a variety of novel siloxane-containing conjugated semiconductor classes by using a variety of aryldihalides and aryldiboronic acids/esters. Heavy weight: Fluoride-mediated Suzuki polymerizations under conventional and microwave-assisted heating were performed to generate a solution-processable poly(diketopyrrolopyrrole-alt-benzothiadiazole) consisting of the hybrid siloxane substituents. The optimal reaction conditions, in terms of the molecular weights, involved the use of CsF and DME at 120°C with conventional heating for 24 hours