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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Diastereoselective synthesis and ESR study of 4-phenylDEPMPO spin traps
Micaël Hardy1, Florence Chalier, Jean-Pierre Finet
1Laboratoire SREP, UMR 6517 CNRS et Universités Aix-Marseille 1, 2 et 3, Centre de Saint Jérôme, 13397 Marseille Cedex 20, France.
Abstract:
[reaction: see text] The cis and trans diastereoisomers of 5-(diethoxyphosphoryl)-5-methyl-4-phenylpyrroline N-oxide (4-PhDEPMPOt 8 and 4-PhDEPMPOc 9) were prepared stereoselectively and used as spin traps for hydroxyl and superoxide radicals. The spin adduct formed by reaction of the cis stereoisomer 9with superoxide radical anion exhibited an 8-line ESR spectrum, showing only a reduced alternating line width phenomenon. This spectrum is simpler than the 12-line spectrum of DEPMPO-OOH, which exhibits a strong alternating line width phenomenon. The half-life times of the 4-PhDEPMPOc-OOH and DEPMPO-OOH adducts were of the same order: 14.5 and 15.5 min, respectively.
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