Nickel(II)-catalyzed living polymerization of diazoacetates toward polycarbene homopolymer and polythiophene-block-polycarbene copolymers

Abstract

Diazoacetate polymerization has attracted considerable research attention because it is an effective approach for fabricating carbon–carbon (C–C) main chain polymers. However, diazoacetate polymerization based on inexpensive catalysts has been a long-standing challenge. Herein, we report a Ni(II) catalyst that can promote the living polymerization of various diazoacetates, yielding well-defined C–C main chain polymers, polycarbenes, with a predictable molecular weight (Mn) and low dispersity (Mw/Mn). Moreover, the Ni(II)-catalyzed sequential living polymerization of thiophene and diazoacetate monomers affords interesting π-conjugated poly(3-hexylthiophene)-block-polycarbene copolymers in high yields with a controlled Mn, variable compositions, and low Mw/Mn, although the structure and polymerization mechanism of the two monomers differ. Using this strategy, amphiphilic block copolymers comprising hydrophobic poly(3-hexylthiophene) and hydrophilic polycarbene blocks are facilely prepared, which were self-assembled into well-defined supramolecular architectures with tunable photoluminescence.

Synthesis Methodology of End-Functionalized Poly(quinolylene-2,3-methylene)s: Living Cyclocopolymerization Using Aryl Palladium Initiators Conveniently Prepared from Versatile Aryl Halide

“…One method for synthesizing end functional polymers is the introduction of a functional group derived from the initiator (α-chain end) (Figure a). The method is based on living polymerization (e.g., radical, − ionic, , and coordination polymerizations − ), which is practical and efficient because substituents can be reliably introduced into the α-chain end unless a chain transfer reaction occurs. However, it is necessary to prepare an initiator for each substituent and examine the reaction conditions for each initiator.…”

Thermotropic chirality enhancement of nanoparticles constructed from foldamer/bis(amino acid) complexes

“…Artificial foldamers are often used to construct chiral materials because they can fold into a compact helical conformation, [16][17][18][19] which is stabilized by non-covalent interactions such as solvophobic interactions and π-π stacking interactions in the foldamer main chain. 20,21 In particular, they can undergo a conformation transition in response to temperature.…”

Ruthenium-catalyzed diazoacetate/cyclooctene metathesis copolymerization

“…22–25 However, most of the previous works focus on the transition metal-catalyzed polymerization of diazoacetate monomers. 26–33 Nonetheless, the use of diazo compounds has greatly expanded the range of desirable polymers, but their potential applications in the ROMP process have remained largely unexplored. 34…”

“…[22][23][24][25] However, most of the previous works focus on the transition metal-catalyzed polymerization of diazoacetate monomers. [26][27][28][29][30][31][32][33] Nonetheless, the use of diazo compounds has greatly expanded the range of desirable polymers, but their potential applications in the ROMP process have remained largely unexplored. 34 In this paper, we demonstrated the Ru-catalyzed ROMP of COE in the presence of diazoacetate and (bis)diazoacetate compounds; well-defined telechelic polymers and random functionalized copolymers can be accessed under mild conditions (Scheme 1d).…”