Title: Galvinoxyl
CAS Registry Number: 2370-18-5
CAS Name: 4-[[3,5-Bis(1,1-dimethylethyl)-4-oxo-2,5-cyclohexadien-1-ylidene]methyl]-2,6-bis(1,1-dimethylethyl)phenoxy
Additional Names: Coppinger's radical; 2,6-di-tert-butyl-a-(3,5-di-tert-butyl-4-oxo-2,5-cyclohexadiene-1-ylidene)-p-tolyloxy radical; 2,6,3¢,5¢-tetra-tert-butyl-4¢-phenoxy-4-methylene-2,5-cyclohexadiene-1-one radical
Molecular Formula: C29H41O2
Molecular Weight: 421.63
Percent Composition: C 82.61%, H 9.80%, O 7.59%
Literature References: Stable phenoxyl radical. Prepn: G. M. Coppinger, J. Am. Chem. Soc. 79, 501 (1957); M. S. Kharasch, B. S. Joshi, J. Org. Chem. 22, 1435 (1957). Radical scavenging study: P. D. Bartlett, T. Funahashi, J. Am. Chem. Soc. 84, 2596 (1962). Electrical properties: D. D. Eley et al., Trans. Faraday Soc. 62, 3192 (1966). Structure determn: D. E. Williams, Mol. Physics 16, 145 (1969). Resonance Raman study: G. N. R. Tripathi, Chem. Phys. Lett. 81, 375 (1981). Theoretical study of magnetic interactions: F. Dietz et al., J. Phys. Chem. B 102, 3912 (1998). Ab initio studies of ferromagnetic properties: S. J. Luo, K. L. Yao, J. Magn. Magnet. Mater. 257, 11 (2003). Use in detection of phospholipid phase transitions: M. A. Singer et al., Anal. Biochem. 94, 322 (1979). Use in measurement of hydrogen-donating activity and antioxidant activity in phenols: H. Shi et al., Methods Enzymol. 335, 157 (2001).
Properties: Deep blue needles from absolute ethanol, mp 157.5° (Kharasch, Joshi). Also reported as dark blue needles from dry ethanol, mp 153° (Eley). Absorption max (iso-octane): 280, 289, 400, 423 nm (e ´103 9.39, 9.4, 24.3, 180.0). Absorption max (benzene): 407 nm, 431 nm (e 30000, 154000). Absorption max (ethanol): 428 nm. Sol in petr ether, benzene, cyclohexane.
Melting point: mp 157.5° (Kharasch, Joshi); mp 153° (Eley)
Absorption maximum: Absorption max (iso-octane): 280, 289, 400, 423 nm (e ´103 9.39, 9.4, 24.3, 180.0); Absorption max (benzene): 407 nm, 431 nm (e 30000, 154000); Absorption max (ethanol): 428 nm
Use: Free radical scavenger.
Gamabufotalin Gambir Gambogic Acid gamma-Carboline gamma-Carboxyglutamic Acid

Molecular formula C29H41O2
Molar mass 421.63 g mol−1
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Galvinoxyl is a commercially available free radical inhibitor. It may be synthesized by oxidation of the parent phenol with lead dioxide or potassium hexacyanoferrate(III). Its radical structure is confirmed by the loss of the O-H stretch in the IR spectrum and by electron spin resonance; it is stable even in the presence of oxygen.[1][2]