Synthesis and Characterizations of Polythiophene Networks with Nonplanar BN Lewis Pair Building Blocks

Abstract

Doping the boron (B) element endowed organic π-conjugated polymers (OCPs) with intriguing optoelectronic properties. Herein, we introduce a new series of thienylborane-pyridine (BN) Lewis pairs via the facile reactions between thienylborane and various pyridine derivatives. Particularly, we developed a “one-pot” synthetic protocol to access BN2 with an unstable 4-bromopyridine moiety. Polycondensations between the BN Lewis pairs and distannylated thiophene afforded a new series of BN-cross-linked polythiophenes (BN-PTs). Experiments revealed that BN-PTs exhibited highly uniform chemical structures, particularly the uniform chemical environment of B-centers. BN-PTs showed good stability in the solid state. PBN2 even maintained the uniform B-center under high temperature or moisture conditions. The studies further suggested that the presence of topological BN structures endowed the polymers with strong intramolecular charge separation character. As a proof of concept, a representative BN-PT was tested as the catalyst for photocatalytic hydrogen evolution.

Boron‐Nitrogen Lewis Pairs in the Assembly of Supramolecular Macrocycles, Molecular Cages, Polymers, and 3D Materials

“…Recently, the strong binding of pyridines to triarylboranes has been exploited in the development of new robust COF materials with π‐conjugated structures [64] . For instance, Ren and co‐workers showed that complexes of tris(5‐bromothien‐2‐yl)borane with 4‐bromopyridine, 4,4′‐bipyridine or 1,3,5‐tris(pyridyl)benzene are amenable to Stille coupling polymerization with distannylated thiophene to produce COF materials with B−N LPs as crosslinking points [65] . The products showed interesting low energy ICT absorptions and one of the COFs was studied for photocatalytic H 2 production.…”

Boron‐Nitrogen Lewis Pairs in the Assembly of Supramolecular Macrocycles, Molecular Cages, Polymers, and 3D Materials

“…[64] For instance, Ren and co-workers showed that complexes of tris(5bromothien-2-yl)borane with 4-bromopyridine, 4,4'-bipyridine or 1,3,5-tris(pyridyl)benzene are amenable to Stille coupling polymerization with distannylated thiophene to produce COF materials with BÀ N LPs as crosslinking points. [65] The products showed interesting low energy ICT absorptions and one of the COFs was studied for photocatalytic H 2 production.…”

Amorphous porous organic polymers containing main group elements

“…The high Lewis acidity of thienylborane towards various pyridine moieties (such as 4-bromopyridine, 4,4’-bipyridine, and 1,3,5-tri(pyridinyl)benzene) further inspired Ren and coworkers to design new thienylboran-pyridine (TB-py) Lewis pairs (Fig. 5a ) 71 . BN-crosslinked polythiophene networks with the diverse topological TB-py Lewis pairs were constructed by using typical Stille type coupling reaction (Fig.…”