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  • Synthesis of 1,2-Oxazinanes via Hydrogen Bond Mediated [3 + 3] Cycloaddition Reactions of Oxyallyl Cations with Nitrones
Title: Synthesis of 1,2-Oxazinanes via Hydrogen Bond Mediated [3 + 3] Cycloaddition Reactions of Oxyallyl Cations with Nitrones
Reported herein is the development of [3 + 3] cycloaddition reactions between oxyallyl cations and nitrones to yield 1,2-oxazinane heterocycles. Oxyallyl cation intermediates, generated in situ from α-tosyloxy ketones in the presence of hexafluoro-2-propanol (HFIP), a cosolvent, and a base, are found to react with a range of nitrones to afford 1,2-oxazinanes in good to high yields. The reactions are catalyzed by hydrogen-bond donors such as phenols and squaramides, and dramatically higher diastereoselectivities are observed with 4-nitrophenol.  more » « less
Award ID(s):
1566402
PAR ID:
10338213
Author(s) / Creator(s):
; ;
Editor(s):
Smith, Amos B.
Date Published:
Journal Name:
Organic letters
Volume:
20
Issue:
17
ISSN:
1523-7060
Page Range / eLocation ID:
5384–5388
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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