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Stereoselective photoredox ring-opening polymerization of O-carboxyanhydrides.

ABSTRACT: Biodegradable polyesters with various tacticities have been synthesized by means of stereoselective ring-opening polymerization of racemic lactide and ?-lactones but with limited side-chain groups. However, stereoselective synthesis of functional polyesters remains challenging from O-carboxyanhydrides that have abundant pendant side-chain functional groups. Herein we report a powerful strategy to synthesize stereoblock polyesters by stereoselective ring-opening polymerization of racemic O-carboxyanhydrides with the use of photoredox Ni/Ir catalysts and a selected Zn complex with an achiral ligand. The obtained stereoblock copolymers are highly isotactic with high molecular weights (?>?70?kDa) and narrow molecular weight distributions (Mw/Mn?

SUBMITTER: Feng Q

PROVIDER: S-EPMC5908805 | biostudies-other | 2018 Apr

REPOSITORIES: biostudies-other

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Stereoselective photoredox ring-opening polymerization of O-carboxyanhydrides.

Feng Quanyou Q Yang Lei L Zhong Yongliang Y Guo Dong D Liu Guoliang G Xie Linghai L Huang Wei W Tong Rong R

Nature communications 20180419 1

Biodegradable polyesters with various tacticities have been synthesized by means of stereoselective ring-opening polymerization of racemic lactide and β-lactones but with limited side-chain groups. However, stereoselective synthesis of functional polyesters remains challenging from O-carboxyanhydrides that have abundant pendant side-chain functional groups. Herein we report a powerful strategy to synthesize stereoblock polyesters by stereoselective ring-opening polymerization of racemic O-carbox ...[more]

PMID: 29674720

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