The Marriage of Metallacycle Transfer Chemistry with Suzuki–Miyaura Cross-Coupling To Give Main Group Element-Containing Conjugated Polymers

Abstract

A versatile and general synthetic route for the synthesis of conjugated main group element-based polymers, previously inaccessible by conventional means, is reported. These polymers contain five-membered chalcogenophene rings based on S, Se, and Te, and we demonstrate that optoelectronic properties can be readily tuned via controlled atom substitution chemistry. In addition, regioregular hybrid thiophene-selenophene-tellurophene and selenophene-fluorene copolymers were synthesized to provide a further illustration of the scope of the presented metallacycle transfer/cross-coupling polymerization method.

Tellurophenes and Their Emergence as Building Blocks for Polymeric and Light-emitting Materials

“…The molecular weights of these polymers ranged from 5.4 to 11.3 kDa, as determined by GPC in trichlorobenzene (140°C). Consistent with prior polychalcogenophenes containing the heavier elements Se and Te, 14 intense UV absorptions with ¾ = 39006400 M ¹1 cm ¹1 per repeat unit were found. Specifically, poly(3-hexyltellurophene) (13a) displays an absorption centered at 599 nm with a shoulder present at ca.…”

Electrochromic Poly(chalcogenoviologen)s as Anode Materials for High‐Performance Organic Radical Lithium‐Ion Batteries

“…[5] Owing to their synthetic versatility and the ready tunability of their redox properties, [6] the development of viologen-based energy-storage devices has increased dramatically over the past decades. [17] However,t he inherent toxicity and shortage of heavychalcogenide resources may limit their application. [12] As ap romising emerging technology for energy storage, [13] ORBs have shown several advantages as compared to previously reported inorganic [14] and polymeric materials, [15] such as no need for rare metals,r eady tunability of redox properties,g reater safety,a nd design flexibility at the molecular level, but the development of such batteries has still been limited.…”

“…[16] Reported ORBs suffered from poor performance,f or example,l ow cell capacity and stability, owing to fewer redox states and low specific energy.T herefore,t he development of novel viologen derivatives with multiple stable redox centers and higher specific energy could dramatically enhance the performance and expand the limits of ORBs. [17] However,t he inherent toxicity and shortage of heavychalcogenide resources may limit their application. [17] However,t he inherent toxicity and shortage of heavychalcogenide resources may limit their application.…”

Narrow‐Bandgap Chalcogenoviologens for Electrochromism and Visible‐Light‐Driven Hydrogen Evolution

“…Thes ynthesis of chalcogenoviologens were obtained by treatment of 1 [10a] with n BuLi, followed by addition of S 2 Cl 2 , [18] SeCl 2 [19] or Te Cl 4 . [20] Thieno[2,3-c:5,4-c']bipyridine (2a)w as obtained in 36 %yield; [21] selenopheno[2,3-c:5,4-c']bipyridine (2b)a nd telluropheno[2,3-c:5,4-c']bipyridine (2c)w ere synthesized for the first time with the moderate yield of 44 %and 57 %, respectively.L ow-field shift of 1 Hr esonances was observed from 9.28 to 9.18 on the a-pyridine protons with the introduction of heavier atoms.Chalcogen-bridged bipyridine 2 was converted into the chalcogen-MV 2+ 3 through reaction with methyl triflate (MeOTf), which were obtained as asolid (3a:o ff-white,w hich was reported previously, [22] 3b:d ark green, 3c:d ark red) in ah igh yield of ca.…”