2,2,6,6-Tetramethyl-1-oxopiperidinetribromide and two forms of 1-hydroxy-2,2,6,6-tetramethylpiperidinium bromide salt: Syntheses, crystal structures and theoretical calculations

Synthesis of N-Heterocyclic Analogues of 28-O-Methyl Betulinate, and Their Antibacterial and Antifungal Properties

“…2,2,6,6-Tetramethyl-1-oxopiperidinium tribromide was obtained as dark-red crystals, which were formed in the reaction of 0.05 mol of TEMPO radical with 0.08 mol of Br 2 in dry CCl 4 . Physico-chemical characteristics of the obtained compound Tempo + Br 3 − correspond to those described in the literature [13][14][15]. Starting triterpenoid 1 was prepared as previously reported [16].…”

Isolation and X-ray Crystal Structure of an Electrogenerated TEMPO–N3 Charge-Transfer Complex

“…Although crystal structures of (TEMPO + X – )-type CTCs have been reported by mixing TEMPO with a strong oxidant (e.g., Br 2 or quinone derivatives), these structures display an N–O bond distance of ca. 1.19 Å that is characteristic of TEMPO + with no apparent structural distortions or molecular interactions between the oxoammonium ion and the counteranion (X – ) beyond ion pairing. , These features indicate near-complete charge transfer from TEMPO to the oxidant and thus are distinct from the TEMPO–N 3 CTC that we report herein.…”

Iron(iv) complexes with tetraazaadamantane-based ligands: synthesis, structure, applications in dioxygen activation and labeling of biomolecules

“…1350 cm −1 for nitroxide radicals 38 and ca. 1600 cm −1 for oxoammonium cations 35 ). Overall, the observed structural metrics and IR spectroscopy data are more consistent with the Fe IV –( − O–N) structure rather than with the presence of an iron-nitroxide radical bonding Fe III –(˙O–N) or coordinated oxoammonium Fe II –(ON + ).…”