학술논문
Studies on Difficult Intramolecular Hydroaminations in the Context of Four Syntheses of Alkaloid Natural Products.
Document Type
Article
Author
Source
Subject
*HYDROAMINATION
*INTRAMOLECULAR catalysis
*ORGANIC synthesis
*RING formation (Chemistry)
*HYDROXYLAMINE
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Language
ISSN
0022-3263
Abstract
Examples of intramolecular alkene hydroaminations forming six-membered ring systems are rare, especially for systems in which the double bond is disubstituted. Such cyclizations have important synthetic relevance. Herein we report a systematic study of these cyclizations using recently developed Cope-type hydroamination methodologies. Difficult intramolecular alkene hydroaminations were used as key steps in syntheses of 2-epi-pumiliotoxin C, coniine, N-norreticuline and desbromoarborescidine A. This effort required the development of optimized hydroamination conditions to improve the efficiency of the cyclizations. Collectively, our results show that Cope-type cyclizations can be achieved on a variety of challenging substrates and proceed under similar conditions for both N-H and N-substituted hydroxylamines. [ABSTRACT FROM AUTHOR]