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Stereoselective isoxazolidine synthesis via copper-catalyzed alkene aminooxygenation.

ABSTRACT: Isoxazolidines are useful in organic synthesis, drug discovery, and chemical biology endeavors. A new stereoselective synthesis of methyleneoxy-substituted isoxazolidines is disclosed. The method involves copper-catalyzed aminooxygenation/cyclization of N-sulfonyl-O-butenyl hydroxylamines in the presence of (2,2,6,6-tetramethylpiperidin-1-yl)oxyl radical (TEMPO) and O(2) and provides substituted isoxazolidines in excellent yields and diastereoselectivities. We also demonstrate selective mono N-O reduction followed by oxidation of the remaining N-O bond to reveal a 2-amino-?-lactone. Reduction of the ?-lactone reveals the corresponding aminodiol.

SUBMITTER: Karyakarte SD

PROVIDER: S-EPMC3465949 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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Stereoselective isoxazolidine synthesis via copper-catalyzed alkene aminooxygenation.

Karyakarte Shuklendu D SD Smith Thomas P TP Chemler Sherry R SR

The Journal of organic chemistry 20120815 17

Isoxazolidines are useful in organic synthesis, drug discovery, and chemical biology endeavors. A new stereoselective synthesis of methyleneoxy-substituted isoxazolidines is disclosed. The method involves copper-catalyzed aminooxygenation/cyclization of N-sulfonyl-O-butenyl hydroxylamines in the presence of (2,2,6,6-tetramethylpiperidin-1-yl)oxyl radical (TEMPO) and O(2) and provides substituted isoxazolidines in excellent yields and diastereoselectivities. We also demonstrate selective mono N-O ...[more]

PMID: 22870912

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