Azides are infrared (IR) probes that are important for structure and dynamics studies of proteins. However, they often display complex IR spectra owing to Fermi resonances and multiple conformers. Isotopic substitution of azides weakens the Fermi resonance, allowing more accurate IR spectral analysis. Site-specifically 15N-labeled aromatic azides, but not aliphatic azides, are synthesized through nitrosation. Both 15N-labeled aromatic and aliphatic azides are synthesized through nucleophilic substitution or diazo-transfer reaction but as an isotopomeric mixture. We present the synthesis of TfNN15N, a γ-15N-labeled diazo-transfer reagent, and its use to prepare β-15N-labeled aliphatic as well as aromatic azides.
Bibliographical noteFunding Information:
H.H. is grateful for financial support from the National Research Foundation (NRF) of Korea funded by the Ministry of Science and ICT (NRF2021R1A2C1094754). M.C. thanks financial support from the Institute for Basic Science (IBS-R023-D1). a
© 2021 The Authors. Published by American Chemical Society
ASJC Scopus subject areas
- Chemical Engineering(all)