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.murray
amgen.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
see article for more reactions
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.
see article for more examples
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
