https://www.cas.cn/syky/202503/t20250318_5050549.shtml

https://www.nature.com/articles/s41557-025-01751-w

A research group of the CAS Shanghai Institute of Organic Chemistry has discovered that the simple commercial aromatic compound coumarin is a new type of pro-degradation unit and can effectively solve the challenges of biodegradability. The team used B(2,4-F2C6H3)3 and PtBu3 hindered Lewis acid and base as new synergistic catalysts to achieve efficient, active, and alternating copolymerization of coumarin and acrylate, and constructed a class of all-carbon main-chain polymers with precisely controllable molecular weight, terminal, and sequence structure, and the number average molecular weight reached 236.5 kg/mol. At the same time, theoretical calculations showed that thermodynamic control was the reason for the formation of alternating sequences. The study found that the new all-carbon main-chain polymer has optical properties comparable to or even better than those of organic glass, and its thermal and mechanical properties are adjustable over a wide range depending on the acrylate side groups, and has excellent solvent resistance and thermal stability.

When 1,5,7-triazidobicyclo (4.4.0) dec-5-ene (TBD) or Cs2CO3 is used as a strong base catalyst, the all-carbon main-chain polymer can be degraded on demand at room temperature, and dimerized small molecules with biomedical value can be quantitatively recovered. In particular, all-carbon main-chain polymers with room-temperature quantitative degradation capabilities are very rare. Mechanistic studies have shown that the aromatization process from the 6π-electron coumarin addition fragment to the 10π-electron coumarin-derived dimer provides a thermodynamic driving force for the efficient and highly selective cleavage of the full carbon backbone, establishes a new strategy for aromatization-driven carbon chain cleavage, and provides a new idea for the quantitative degradation of difficult-to-degrade full-carbon backbone polymers under mild conditions.