Ipso Nitration of Aryl Boronic Acids Using Fuming Nitric Acid
James I. Murray*, Maria V. Silva Elipe, Kyle D. Baucom, Derek B. Brown, Kyle Quasdorf and Seb Caille
*Drug Substance Technologies, Process Development, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States, Email: j.murrayamgen.com
J. I. Murray, M. V. Silva Elipe, K. D. Baucom, D. B. Brown, K. Quasdorf, S. Caille, J. Org. Chem., 2022, 87, 1977-1985.
DOI: 10.1021/acs.joc.1c00886
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Abstract
An ipso nitration of aryl boronic acid derivatives using fuming nitric acid as the nitrating agent provides efficient and chemoselective access to a variety of aromatic nitro compounds. Preliminary reported reactions with different activating agents likely generate anhydrous HNO3 as common active reagent and the •NO2 radical as the active species too.
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proposed reaction pathway
Note
The reaction exhibits some unusual autocatalytic kinetics that result in a terminal exotherm from decomposition of excess HNO3. We wanted to make sure the community is aware of this. See Org. Process Res. Dev. 2022, 26, 657-660.
James I. Murray, November 1, 2022
Key Words
ID: J42-Y2022