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Tandem diaza-Cope rearrangement polymerization: turning intramolecular reaction into powerful polymerization to give enantiopure materials for Zn²⁺ sensors.

ABSTRACT: [3,3]-Sigmatropic rearrangement is a powerful reaction to form C-C bonds stereospecifically; however, owing to intrinsic simultaneous bond formation and breakage, this versatile method has not been utilized in polymerization. Herein, we report a new tandem diaza-Cope rearrangement polymerization (DCRP) that can synthesize polymers with defect-free C-C bond formation from easy and efficient imine formation. A mechanistic investigation by in situ ¹H NMR experiments suggests that this polymerization proceeds by a rapid DCR process, forming an enantiospecific C-C bond that occurs almost simultaneously with imine formation. This polymerization produces not only highly stable polymers against hydrolysis due to resonance-assisted hydrogen bonds (RAHBs) but also chiral polymers containing enantiopure salen moieties, which lead to high-performance Zn²⁺-selective turn-on chemosensors with up to 73-fold amplification. We also found that their optical activities and sensing performances are heavily dependent on the reaction temperature, which significantly affects the stereoselectivity of DCR.

SUBMITTER: Hwang SH

PROVIDER: S-EPMC8179250 | biostudies-literature |

REPOSITORIES: biostudies-literature

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