Abstract
We have developed a highly stereospecific cyclization of aziridine silanols into 1′-amino-tetrahydrofurans. Our protocol of stirring a substrate with 10 mol % Sc (OTf)3 and 1 equivalent of NaHCO3 in CH2Cl2 is mild and compatible with a range of activating aziridine N-substituents (including tosylates, mesylates, and carbamates) and functional groups on the alkyl chains (including substituted aryl rings, alkyl bromides, and alkyl ethers). In all cases examined, trans di-substituted aziridine silanols give products with an erythro configuration; conversely, cis di-substituted aziridine silanols give products with a threo configuration. While literature syntheses of 1′-amino-tetrahydrofurans exist, only one example, contemporaneous with our work, uses a similar cyclization for their construction. Control experiments demonstrate that, for this transformation, the silanol is not particularly privileged, and a variety of protecting groups on the alcohol (including other silicon protecting groups, benzyl ethers, and MOM ethers) are compatible with product formation.
Description
This document is the Accepted Manuscript version of a Published Work that appeared in final form in The Journal of Organic Chemistry, Copyright © 2023 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.joc.3c00763.
Citation
Nirpal, A. K., Nagamalla, S., Mague, J. T., & Sathyamoorthi, S. (2023). Ring Opening of Aziridines by Pendant Silanols Allows for Stereospecific Preparations of 1'-Amino-tetrahydrofurans. The Journal of organic chemistry, 88(13), 9136–9156. https://doi.org/10.1021/acs.joc.3c00763