AI Article Synopsis
- Lai's synthesis protocol for nitroxides has been adapted to create new chiral piperazine and morpholine nitroxides.
- The Bargellini reaction serves as the critical step in forming these new compounds.
- Among the synthesized compounds, one, known as compound 43, was observed to racemize under mild oxidizing conditions, prompting an investigation into the racemization mechanism.
Article Abstract
Lai's protocol for the synthesis of nitroxides has been extended to the synthesis of several new chiral piperazine and morpholine nitroxides. This strategy utilizes the Bargellini reaction as the key bond-forming step. Several optically pure nitroxides incorporating alpha-aromatic and alpha-spiro centers were prepared by this route. These chiral nitroxides will be of interest as enantioselective oxidants, as traps for prochiral radicals, and in the preparation of new materials. One of these nitroxides, compound 43, was found to racemize under mild oxidizing conditions. The mechanism for this unusual racemization reaction was investigated.
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