In 2022,Hu, Zhitao; Cao, Xiaohui; Zhang, Xiaohui; Wu, Bin; Luo, Wenjun; Huang, Huahua; Li, Le; Chen, Yongming published an article in ACS Macro Letters. The title of the article was 《Catalytically Controlled Ring-Opening Polymerization of 2-Oxo-15-crown-5 for Degradable and Recyclable PEG-Like Polyesters》.Computed Properties of C10H20O5 The author mentioned the following in the article:
Poly(ethylene glycol) (PEG) has been extensively used in diverse applications. However, it is not biodegradable and shows abnormal immune responses. Herein, a fast, controlled, ring-opening polymerization (ROP) of 2-oxo-15-crown-5 (O-15C5) is reported to prepare well-defined PEG-like polyesters, poly(O-15C5). This approach relies on a coordination between the macrocyclic monomer and Na+ that increases the electrophilicity of the carbonyl group of O-15C5 and leads to a fast controlled ROP (dispersity, DM < 1.2). Both computational and mechanistic studies show that the selective Na+ binding to the monomer over poly(O-15C5) allows the ring-opening initiation and propagation to be more energetically favorable than side transesterifications. This is the key to control the challenging entropy-driven ROP of O-15C5. Moreover, with the aid of Na+ and organic base, poly(O-15C5) depolymerized readily into O-15C5 in 2 h. Also, it degraded in a buffer of pH 7.4 by hydrolysis. After reading the article, we found that the author used 1,4,7,10,13-Pentaoxacyclopentadecane(cas: 33100-27-5Computed Properties of C10H20O5)
1,4,7,10,13-Pentaoxacyclopentadecane(cas: 33100-27-5) is a member of crown ether Ligands. Crown-ethers are macrocyclic polyethers capable of forming host-guest complexes, especially with inorganic and organic cations. Crown-ethers can incorporate protonated primary amine compounds by formation of ion-dipole bonds with the oxygen atoms of the chiral selector. Crown-ethers have been widely used for the separation of several pharmaceuticals both in aqueous and non-aqueous media. Computed Properties of C10H20O5
Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem