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Updated: Nov 2, 2025
08:46
Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
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Benchtop-Stable Hypervalent Bromine(III) Compounds: Versatile Strategy and Platform for Air- and Moisture-Stable
Kazunori Miyamoto1,2, Motomichi Saito2, Shunsuke Tsuji2
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|June 14, 2021
Summary
Researchers developed a new strategy for synthesizing stable lambda-3 bromanes. This breakthrough allows for the creation of various air- and moisture-stable bromine(III) compounds for diverse applications.
Area of Science:
- Synthetic organic chemistry
- Hypervalent iodine and bromine chemistry
Background:
- Lambda-3 bromanes are reactive and unstable compounds.
- Existing synthetic methods for bromanes are limited.
Purpose of the Study:
- To develop a novel strategy for synthesizing air/moisture-stable lambda-3 bromanes.
- To characterize the structure and stability of these novel bromane derivatives.
Main Methods:
- Cyclic 1,2-benzbromoxol-3-one (BBX) strategy for bromane synthesis.
- X-ray crystallography, NMR, and IR spectroscopy for structural elucidation.
Main Results:
- Successful synthesis of air/moisture-stable lambda-3 bromanes (9 and 10).
- Demonstrated stabilization of the bromine(III) center via intramolecular R-Br-O hypervalent bonding in N-triflylimino-lambda-3-bromane (12).
- Generated diverse stable derivatives including Br-hydroxy, -acetoxy, -alkynyl, -aryl, and bis[(trifluoromethyl)sulfonyl]methylide lambda-3 bromanes.
Conclusions:
- The BBX strategy provides a robust method for accessing stable lambda-3 bromanes.
- Intramolecular hypervalent bonding is key to the observed stability.
- This work expands the scope of stable hypervalent bromine compounds.
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