Feature ArticleRapid one-pot catalytic synthesis of double-capped oligoesters from lactones

- A rapid one-pot catalytic process for the synthesis of double-capped oligoesters from lactones is described.
- A double-capped oligo(ε-caprolactone) was produced in 94% yield within 5 min at room temperature using lithium amide as a catalyst.
- The process can be used to synthesize more inert biodegradable oligoesters suitable for bioplasticizers, green solvents and perfumes.

The rapid one-pot catalytic synthesis of double-capped oligoesters was carried out by the ring-opening polymerization of various cyclic ester monomers (i.e. ε-caprolactone (ε-CL), δ-valerolactone (DVL), γ-butyrolactone (GBL), and L-lactide (L-LA)) followed by the transesterification reaction with a variety of alkyl esters as an end-capping agent. Simple metal amides were found to be an effective catalyst under mild condition. Among them, LiN(SiMe3)2 was shown to be the most active catalyst giving 94% conversion of double-capped oligo(ε-caprolactone) within 5 min at room temperature. The average chain length of the oligoesters can be controlled by the adjustment of the ratio of an alkyl ester to monomer, the reaction time and reaction temperature.

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