Polymeric pseudo-crown ether for cation recognition via cation template-assisted cyclopolymerization

Abstract

Cyclopolymerization is a chain polymerization of bifunctional monomers via alternating processes of intramolecular cyclization and intermolecular addition, to give soluble linear polymers consisting of in-chain cyclic structures. Though cyclopolymers comprising in-chain multiple large rings potentially show unique functionality, they generally require the elaborate design of bifunctional monomers. Here we report cation template-assisted cyclopolymerization of poly(ethylene glycol) dimethacrylates as an efficient strategy directly yielding polymeric pseudo-crown ethers with large in-chain cavities (up to 30-membered rings) for selective molecular recognition. The key is to select a size-fit metal cation for the spacer unit of the divinyl monomers to form a pseudo-cyclic conformation, where the two vinyl groups are suitably positioned for intramolecular cyclization. The marriage of supramolecular chemistry and polymer chemistry affords efficient, one-pot chemical transformation from common chemical reagents with simple templates to functional cyclopolymers.

Sequence-Regulated Polymers via Living Radical Polymerization: From Design to Properties and Functions

“…Focusing on the cation recognition properties (42), we have developed cation template-assisted cyclopolymerization of PEG dimethacrylates with a precision PEG spacer [PEGnDMA, PEG spacer: -O(CH 2 CH 2 O) n -; n = 4, 5, 6,8]. This is a one-pot approach to produce cyclopolymers with in-chain large cyclized PEGs (PPEGnDMAs), "polymeric pseudo-crown ethers", for efficient and selective cation recognition ( Figure 5) (14). The point is to select a size-fit metal cation for PEGnDMA, assuming that the PEG spacer interacts with a metal cation to dynamically form pseudo cyclic monomers bringing two olefins at close position.…”

Cyclopolymerization of a bisacrylate through selective formation of a 19-membered ring

“…However, the low concentration often limits the yields of polymers. 4,9 Effective strategies for improvement of the cyclization tendency involve conformational orientation of two polymerization groups with cyclic structures [10][11][12][13][14][15][16][17][18][19][20][21] or templates such as metal cations 22,23 and selective alternating copolymerization. 24,25 In the most common method, namely, the design of oriented monomers, additional constraints by steric hindrance 12,13,19 and hydrogen bonding 17 are effective in improving the cyclization tendency.…”

Twisting poly(3-substituted thiophene)s: cyclopolymerization of gemini thiophene monomers through catalyst-transfer polycondensation

“…However, with an elaborate monomer design, large macrocycles can be produced, thus resulting in polymeric materials with the capacity of molecular recognition. [3][4][5][6][7][8] In addition, the alternating propagation process can be exploited for sequence control in a polymer main chain. 9,10 As such, cyclopolymerization is an intriguing polymerization methodology that allows access to novel polymer structures.…”