Chiral N-Acyloxazolidines: Synthesis, Structure, and Mechanistic Insights

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• 作者：Martí ; n &Aacute ; valos ; Reyes Babiano ; Pedro Cintas ; José ; L. Jimé ; nez ; Mark E. Light ; Juan C. Palacios ; Esther M. S. Pé ; rez
• 刊名：Journal of Organic Chemistry
• 出版年：2008
• 出版时间：January 18, 2008
• 年：2008
• 卷：73
• 期：2
• 页码：661 - 672
• 全文大小：300K
• 年卷期：v.73,no.2(January 18, 2008)
• ISSN：1520-6904

文摘

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A series of chiral imines derived from 1-amino-1-deoxyalditols such as D-glucamine, a rather unexploredraw material from the chiral pool, have been serendipitiously transformed into a novel family of N-acetyl-1,3-oxazolidines by means of an unexpected acetylation. The structure of these substances is supportedby spectroscopic and crystallographic data. The acetylates also trigger a complex dynamic transformation,in which an initially configured trans oxazolidine converts into a more stable cis-configured derivative.Both isomers can also exist as rotational conformers (E,Z) as a consequence of the restricted rotationaround the N-acetyl bond. The barriers to rotation have been determined by variable-temperatureexperiments. Overall, this transformation most likely involves the intermediacy of a chiral iminium ion,which has been documented in the synthesis of nitrogen heterocycles, thus explaining the experimentalfacts.