Highly Efficient Incorporation of Functional Groups into Aromatic Main-Chain Polymer Using Iridium-Catalyzed C−H Activation and Suzuki−Miyaura Reaction

Abstract

We report a mild, iridium-catalyzed borylation of aromatic polysulfone with bis(pinacolato)diboron [B(2)(pin)(2)] to form the corresponding borylated polysulfones up to high concentrations with nearly constant efficiency. The Suzuki-Miyaura cross-coupling reactions of the borylated polysulfones with functionalized aryl bromides allows installation of various functional groups such as ketone, amine, hydroxyl, and aldehyde to the polysulfone main chain in excellent conversion.

Recent advances in the preparation of functionalized polysulfones

“…In contrast to traditional free radical mediated polymer functionalization, in which undesired side reactions commonly alter the properties of the functionalized polymers, the combination of iridium-catalyzed activation/borylation of the aromatic C−H bond and the Suzuki−Miyaura cross-coupling reaction yielded functionalized polysulfones without noticeable changes in the molecular weights of the starting polymers. 236 The pendant pinacolboronate functionalized polysulfone was obtained in good yield via iridiumcatalyzed C−H activation/borylation of the aromatic C−H bond. Because a boron moiety in polymers can serve as a versatile intermediate for conversions to various functional groups, the pinacolboronate ester groups were subsequently transformed to ketone, amine, tert-butyloxycarbonyl-protected amine, hydroxy and aldehyde groups via the Suzuki−Miyaura cross-coupling reaction (Scheme 14).…”

“…In contrast to traditional free radical mediated polymer functionalization, in which undesired side reactions commonly alter the properties of the functionalized polymers, the combination of iridium‐catalyzed activation/borylation of the aromatic C−H bond and the Suzuki−Miyaura cross‐coupling reaction yielded functionalized polysulfones without noticeable changes in the molecular weights of the starting polymers . The pendant pinacolboronate functionalized polysulfone was obtained in good yield via iridium‐catalyzed C−H activation/borylation of the aromatic C−H bond.…”

Direct access to functional (Meth)acrylate copolymers through transesterification with lithium alkoxides

“…Ideally, the direct transformation of commodity homopolymers into functional copolymers would overcome these challenges and provide an efficient platform for material development . To demonstrate the potential of this approach, PMMA was selected as a candidate material due to the high availability from commercial sources or synthesis using anionic or radical polymerization processes.…”

Mixed-donor N,N,O-tridentate ligands for palladium-catalyzed Suzuki reactions

“…The 2010 Nobel prize in chemistry was awarded to Suzuki for his discovery and development of the Suzuki reaction for biaryls [3]. The development of improved reaction conditions for the Pd-catalyzed Suzuki reaction has received much attention recently [4][5][6]. The choice of ligand is known to be crucial to the success of such a catalytic reactions.…”