“Benchtop” Biaryl Coupling Using Pd/Cu Cocatalysis: Application to the Synthesis of Conjugated Polymers

Abstract

Typically, Suzuki couplings used in polymerizations are performed at raised temperatures in inert atmospheres. As a result, the synthesis of aromatic materials that utilize this chemistry often demands expensive and specialized equipment on an industrial scale. Herein, we describe a bimetallic methodology that exploits the distinct reactivities of palladium and copper to perform high yielding aryl–aryl dimerizations and polymerizations that can be performed on a benchtop under ambient conditions. These couplings are facile and can be performed by simple mixing in the open vessel. To demonstrate the utility of this method in the context of polymer synthesis: polyfluorene, polycarbazole, polysilafluorene, and poly­(6,12-dihydro-dithieno­indaceno­dithiophene) were created at ambient temperature and open to air.

Visible Light-Driven, Gold(I)-Catalyzed Preparation of Symmetrical (Hetero)biaryls by Homocoupling of Arylazo Sulfones

“…Purification was carried out by silica gel chromatographic column (eluant: neat cyclohexane) to afford 74.4 mg of 6 (73% yield, slightly yellow solid, mp = 202–203 °C). Spectroscopic data were in accordance with the literature data …”

“…Spectroscopic data were in accordance with the literature data. 43 1 H NMR (300 MHz, CDCl 3 ) δ 7.61 (d, J = 8.6 Hz, 4H), 7.13 (d, J = 8.6 Hz, 4H). 13 C{ 1 H} NMR (75 MHz, CDCl 3 ) δ 139.5, 138.2, 128.8, 93.6.…”

“…2,2′-Bipyridine (43). From 92.50 mg (0.500 mmol) of 1ap, 25.0 mg (0.05 mmol, 10 mol %) of (PPh 3 )AuCl, 40.0 mg of NaHCO 3 (1.0 mmol), and 40.0 mg of 1,10-phenanthroline (0.2 mmol, 40 mol %) in 5 mL of degassed acetonitrile/water (9:1).…”

N-Coordinated Organoboron in Polymer Synthesis and Material Science

“…The applications of boranes and boronic acids/esters in polymer science can be divided into polymer synthesis and the functionalization of polymers. In polymer synthesis, borane and boronic acid/ester can act as a reagent for the polymerization, including as (1) a coinitiator for conventional or controlled radical polymerization, − such as the reversible addition–fragmentation chain-transfer (RAFT) or atom transfer radical polymerization (ATRP) polymerization initiated by boranes; (2) a sacrificial group for the polycondensation, − such as Suzuki–Miyaura polymerization; and (3) cocatalysts in polymerization, such as ring-opening polymerization, frustrated Lewis-pair-catalyzed polymerization, and metal-catalyzed olefin polymerization . As for the functionalization of polymers, the introduction of boronic acid/esters can turn polymers into valuable materials in biomedical, , photoelectric, − sensory, , and self-healing applications.…”

A novel conjugated polymer fluorescence probe for the detection of copper ions in aqueous media

“…However, the high preparation cost and harsh reaction conditions limit the widespread application of CPs. Noble metal catalysts and toxic reagents are necessary for most polymerization reactions, such as for palladium in Suzuki coupling, Heck coupling, and Sonogashira coupling [40][41][42], for organotin reagents in Stille coupling [43], and for nickel chloride in Yamamoto coupling reactions [44]. The low solubility of CPs in aqueous solutions also poses a disadvantage.…”