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Bis-Spiro-Oxetane and Bis-Spiro-Tetrahydrofuran Pyrroline Nitroxide Radicals: Synthesis and Electron Spin Relaxation Studies.

ABSTRACT: Synthesis of bis-spiro-oxetane and bis-spiro-tetrahydrofuran pyrroline nitroxide radicals relies on the Mitsunobu reaction-mediated double cyclizations of N-Boc protected pyrroline tetraols. Structures of the nitroxide radicals are supported by X-ray crystallography. In a trehalose/sucrose matrix at room temperature, the bis-spiro-oxetane nitroxide radical possesses electron spin coherence time, T_m ≈ 0.7 μs. The observed enhanced T_m is most likely associated with strong hydrogen bonding of oxetane moieties to the trehalose/sucrose matrix.

SUBMITTER: Huang S

PROVIDER: S-EPMC10441184 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Bis-Spiro-Oxetane and Bis-Spiro-Tetrahydrofuran Pyrroline Nitroxide Radicals: Synthesis and Electron Spin Relaxation Studies.

Huang Shengdian S Pink Maren M Ngendahimana Thacien T Rajca Suchada S Eaton Gareth R GR Eaton Sandra S SS Rajca Andrzej A

The Journal of organic chemistry 20210921 19

Synthesis of bis-spiro-oxetane and bis-spiro-tetrahydrofuran pyrroline nitroxide radicals relies on the Mitsunobu reaction-mediated double cyclizations of N-Boc protected pyrroline tetraols. Structures of the nitroxide radicals are supported by X-ray crystallography. In a trehalose/sucrose matrix at room temperature, the bis-spiro-oxetane nitroxide radical possesses electron spin coherence time, Tm ≈ 0.7 μs. The observed enhanced Tm is most likely assoc ...[more]

PMID: 34546727

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