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Updated: Jan 10, 2026

Qualitative Identification of Carboxylic Acids, Boronic Acids, and Amines Using Cruciform Fluorophores
Published on: August 19, 2013
Leveraging Long-Range Nuclear Magnetic Resonance Correlations to Confirm Boronic Acid Protection
Tristan Maschmeyer-Tombs1, David J Russell1, Jessica L Ochoa1
1Synthetic Molecule Pharmaceutical Sciences, Genentech, Inc., South San Francisco, California 94080, United States.
Abstract:
The use of boronic acid esters is prevalent in modern synthetic chemistry. However, confirming the protection of boronic acids using chromatographic, spectrometric, and spectroscopic methods can be challenging. In this study, we successfully apply long-range heteronuclear single quantum multiple bond correlation (LR-HSQMBC) NMR experiments to establish through-bond connectivity across protected boronic acid moieties with multiple heteroatoms. The broader applicability of this approach was evaluated using pinacol boronates and N-methyliminodiacetic-acid-protected boronic acids.
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