Rational Monomer Design for the Synthesis of Conjugated Polymers by Direct Heteroarylation Polymerization

Navnath R Kakde; Himanshu Sharma; Nitin V Dalvi; Kumar Vanka; Asha S K

doi:10.1021/acspolymersau.4c00050

Rational Monomer Design for the Synthesis of Conjugated Polymers by Direct Heteroarylation Polymerization

ACS Polym Au. 2024 Jul 5;4(5):449-459. doi: 10.1021/acspolymersau.4c00050. eCollection 2024 Oct 9.

Authors

Navnath R Kakde^{1

2}, Himanshu Sharma^{3

2}, Nitin V Dalvi^{1

2

4}, Kumar Vanka^{3

2}, Asha S K^{1

2}

Affiliations

¹ Polymer Science and Engineering Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India.
² Academy of Scientific and Innovative Research, Sector 19, Kamla Nehru Nagar, Ghaziabad 201002, Uttar Pradesh, India.
³ Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, Maharashtra, India.
⁴ Department of Chemistry, Indian Institute of Science Education and Research (IISER Pune), Pune 411008, Maharashtra, India.

Abstract

This study focuses on the design concepts that contribute to the C-H activation in bithiophene-flanked monomers incorporating naphthalene diimide (NDI), perylene diimide (PDI), and fluorene (FLU) and their polymerization by direct heteroarylation. Density functional theory (DFT) calculations reveal distinct energy requirements for C-H bond abstraction, which is dictated by the electron-withdrawing strength of the central aromatic core flanked by bithiophene. These provide insights into the reactivity of each monomer for C-H bond activation. Proton NMR spectroscopic experimental results confirm the favorable energetic profiles predicted by DFT, with NDI- and PDI-flanked monomers exhibiting lower energy requirements than fluorene-flanked monomers. Successful polymer synthesis is demonstrated for NDI and PDI, while the fluorene-flanked monomer shows challenges due to its higher energy demands.