Synthesis of a 1,2-Dithienylethene-Containing Donor-Acceptor Polymer via Palladium-Catalyzed Direct Arylation Polymerization (DArP).

ABSTRACT: This paper reports the synthesis of D-A polymers containing 1,2-dithienylethene (DTE) units via palladium-catalyzed direct arylation polymerization (DArP). The reaction of dibromoisoindigo (1-Br) and DTE (2-H), in the presence of Pd?(dba)?·CHCl? (0.5 mol%), P(2-MeOC?H?)? (L1) (2 mol%), pivalic acid (1 equiv) as catalyst precursors, and Cs?CO? (3 equiv) as a base affords poly(1-alt-2) with a high molecular weight (Mn up to 44,900). Although, it has been known that monomers, with plural C?H bonds, tend to form insoluble materials via direct arylation at undesirable C?H positions; the reaction of 1-Br and 2-H cleanly proceeds without insolubilization. The resulting polymer has a well-controlled structure and exhibits good charge transfer characteristics in an organic field-effect transistor (OFET), compared to the polymer produced by Migita?Kosugi?Stille cross-coupling polymerization. The DArP product displays an ideal linear relationship in the current?voltage curve, whereas the Migita?Kosugi?Stille product shows a VG-dependent change in the charge mobility.

SUBMITTER: Wakioka M 

PROVIDER: S-EPMC6017491 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature