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Bifunctional phase-transfer catalysts for synthesis of 2-oxazolidinones from isocyanates and epoxides.

ABSTRACT: A series of bifunctional phase-transfer catalysts (PTCs) were synthesized to catalyze the [3 + 2] coupling reaction of isocyanates and epoxides to afford 2-oxazolidinones in good to high yields (up to 92% yield) using PhCl as a solvent at 100 °C within 12 h. These bifunctional PTCs were easily prepared from commercially available tertiary-primary diamines and isocyanates (or isothiocyanates, mono-squaramides, respectively) in two simple steps with good modularity and demonstrated high efficiency (2.5 mol% catalyst-loading). The synergistic interaction of the quaternary ammonium salt center and hydrogen-bond donor group in the catalyst with the substrate is crucial to this atom-economic reaction.

SUBMITTER: Cui DX

PROVIDER: S-EPMC9050849 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Bifunctional phase-transfer catalysts for synthesis of 2-oxazolidinones from isocyanates and epoxides.

Cui Dong-Xiao DX Li Yue-Dan YD Huang Ping P Tian Zhuang Z Jia Yan-Yan YY Wang Ping-An PA

RSC advances 20200326 21

A series of bifunctional phase-transfer catalysts (PTCs) were synthesized to catalyze the [3 + 2] coupling reaction of isocyanates and epoxides to afford 2-oxazolidinones in good to high yields (up to 92% yield) using PhCl as a solvent at 100 °C within 12 h. These bifunctional PTCs were easily prepared from commercially available tertiary-primary diamines and isocyanates (or isothiocyanates, mono-squaramides, respectively) in two simple steps with good modularity and demonstrated high efficiency ...[more]

PMID: 35497599

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