Protonation of Nitramines: Where Does the Proton Go?
Abstract
The reactions of nitramine, N‐methyl nitramine, and N,N‐dimethyl nitramine with anhydrous HF and the superacids HF/MF5 (M=As, Sb) were investigated at temperatures below −40 °C. In solution, exclusive O‐protonation was observed by multinuclear NMR spectroscopy. Whereas no solid product could be isolated from the neat HF solutions even at −78 °C, in the HF/MF5 systems, protonated nitramine MF6− salts were isolated for the first time as moisture‐sensitive solids that decompose at temperatures above −40 °C. In the solid state, depending on the counterion, O‐protonated or N‐protonated cations can be formed, in accord with theoretical calculations which show that the energy differences between O‐protonation and N‐protonation are very small. The salts [H2N‐NO2H][AsF6], [H3N‐NO2][SbF6], [MeHNNO2H][SbF6], and [Me2NNO2H][SbF6] were characterized by their X‐ray crystal structures.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 11, 2017
- Source ID
- 10.1002/anie.201705397
Entities
People
- Karl O. Christe
- Martin Rahm
- Ralf Haiges
- Thomas Saal
Organizations
- Chalmers University of Technology
- Office of Naval Research
- University of Southern California