A Versatile Method for the End‐Functionalization of Polycarbenes

Abstract

End-functionalization is an effective strategy for constructing functional materials. A method for chain-end functionalization of helical polycarbenes is herein developed that relied on Sonogashira coupling reaction. In this work, a family of helical polycarbenes with controlled molecular mass (M n ) and low polydispersity (M w /M n ) is readily prepared using Pd(II) and the Wei-Phos ligand as initiator. The Pd(II) complex is confirmed to remain at the chain end of polycarbene. Subsequently, a series of terminal alkyne derivatives with interesting functional groups, including the F atom, aldehyde, or anthracene groups, are synthesized. They could be installed at the chain end of polycarbene through Sonogashira coupling reaction catalyzed by the Pd(II) complex at the chain end. Moreover, a couple of hybrid block copolymers are easily obtained by installing terminal alkynes modified by another type of polymer. The structures of the isolated polymers are confirmed by 1 H nuclear magnetic resonance ( 1 H NMR), 19 F nuclear magnetic resonance ( 19 F NMR), 31 P nuclear magnetic resonance ( 31 P NMR), and Fourier transform infrared spectroscopy (FT-IR), respectively. The self-assembly properties of the hybrid block copolymers are also investigated by atomic force spectroscopy analysis. By the hereby developed method, various functional groups can be introduced at the chain end of helical polycarbenes for constructing functional polymer materials, moreover, the transition metal residues at the end of polymer chains can be easily removed.

Palladium-Catalyzed Cross-Coupling Polymerization of Bis-N-tosylhydrazones and Bis(silyl) Aryls: A New Access to Polycarbosilane Synthesis

“…The moderate molecular weight might due to the plausible homocoupling, thermal degradation, cyclopropanation, and other side reactions, leading to the undesired consumption of the monomers. 37,45 The structure of P1 was well-defined and confirmed by NMR and FT-IR spectroscopy (Figure 1). The 1 H NMR signals in Figure 1a are quite clear to identify due to their symmetry structure.…”

“…It seems that the molecular weight and PDI were hardly affected. The moderate molecular weight might due to the plausible homocoupling, thermal degradation, cyclopropanation, and other side reactions, leading to the undesired consumption of the monomers. , …”

Porous organic polycarbene nanotrap for efficient and selective gold stripping from electronic waste

“…As a step forwards, "polycarbene", i.e., local assemblies of individual carbene units, have been introduced as versatile materials applied widely in photoluminescence, membrane separation, etc. [19][20][21][22][23] . To upgrade their functions, porous structures have been combined with carbenes to craft intriguing materials as functional porous organic cages and/or actuators in material applications 21,24 .…”

One-pot asymmetric living copolymerization-induced chiral self-assemblies and circularly polarized luminescence

“…[27][28][29][30][31][32][33][34] Therefore, we recently developed chiral Pd(II)-catalysts bearing bidentate phosphine ligands that initiate an asymmetric living polymerization of achiral diazoacetates to give one-handed PAMs with predictable molar masses (M n ) and low dispersities (M w /M n ). [35][36][37][38] We envisioned that the terminal Pd(II)-complex on the synthesized helical PAMs could be subsequently activated to initiate a block copolymerization of aryl monomers and fabricate p-conjugated block copolymers. The helical PAM block would then drive chiral self-assembly of the generated block copolymers during the polymerization, resulting in polymerization-induced selfassembly (PISA).…”