9141. TEMPOL

Nomenclature

CAS number: 2226-96-2
4-Hydroxy-2,2,6,6-tetramethyl-1-piperidinyloxy; 4-hydroxy-TEMPO; 4-hydroxy-2,2,6,6-tetramethyl piperidine N-oxide; 4-hydroxy-2,2,6,6-tetramethylpiperidinooxy.
C9H18NO2; mol wt 172.24.
C 62.76%, H 10.53%, N 8.13%, O 18.58%.

Description and references

Stable nitroxyl radical; water-soluble analogue of TEMPO, q.v. Functions as a membrane-permeable radical scavenger. Prepn: E. G. Rozantsev, Bull. Acad. Sci. USSR Div. Chem. Sci. 12, 2085 (1964). Energy transfer studies: N. N. Quan, A. V. Guzzo, J. Phys. Chem. 85, 140 (1981). IR conformation study: W. A. Bueno, L. Degrève, J. Mol. Struct. 74, 291 (1981). Solid state NMR spectra: C. J. Groombridge, M. J. Perkins, J. Chem. Soc. Chem. Commun. 1991, 1164. LC/MS/MS determn: I. D. Podmore, J. Chem. Res. Synop. 2002, 574. Use as a phase transfer catalyst: X.-Y. Wang et al., Synth. Commun. 29, 157 (1999). Review of effects in animal models for shock, ischemia-reperfusion injury, and inflammation: C. Thiemermann, Crit. Care Med. 31, S76-S84 (2003).

Chemical structure

Properties

Crystals from ether + hexane, mp 71.5°. uv max (hexane): 240, 450-500 (ε ≈1800, ≈5). uv max (ethanol): 242, 435-455 (ε ≈3800, ≈10). Sol in water.

Use

Spin label for EPR studies; phase transfer dehydration catalyst; antioxidant; inhibitor of olefin free radical polymerization.