ESR measurements of the partitioning of some new spin probes inn-octanol-water

Autor: Duncan G. Gillies, Steven E. Bottle, Damien A. Reid, Leslie H. Sutcliffe, Aaron S. Micallef
Rok vydání: 1999
Předmět:
Zdroj: Magnetic Resonance in Chemistry. 37:730-734
ISSN: 1097-458X
0749-1581
DOI: 10.1002/(sici)1097-458x(199910)37:10<730::aid-mrc530>3.0.co;2-e
Popis: The stable free radical 1,1,3,3-tetramethylisoindolin-2-yloxyl (TMIO) has proved to be very suitable for use as a spin probe for a number of applications. Because it is soluble mainly in non-polar liquids, there is a need for new derivatives that can be used in a variety of environments. This has been done by introducing substituents in the 5-position of the aromatic ring, namely carboxyl (CTMIO), trimethylamino (TMTMIOI) and sodium sulphonate (NaTMIOS). An accurate ESR method was developed for the measurement of partition coefficients in n-octanol–water. For comparison purposes the method was also applied to some Tempo derivatives. The effect of temperature on the rotational correlation times and the nitrogen-14 hyperfine coupling constant of some of the spin probes was investigated. There is evidence for dimerization of CTMIO to form a biradical
Databáze: OpenAIRE