Developments in the Separation and Characterisation of Spin Adducts

Considerable effort has been expended by a number of groups to develop robust methodology which can be employed to definitively characterise and quantify spin adducts. Initial studies, for example those of Iwahashi and colleagues, have been reviewed previously. These early studies were concentrated, in the main, on systems where well defined adducts were present, and/or the number of radicals that might be present was limited e.g. refs. 34 and 35). More recently this approach has been developed to examine systems where there are complex mixtures of unknown species. The separation method of choice for this approach 

1-Octanol/water Examples of radicals trapped partition coefficient  

4-PyOPN 121,122 0.18 HO-, Oj--, -CH3, -CHiOH, CH(CH3)0H, co2--. Persistence of adducts strongly pH dependent and greater at acid pH. Half-life of 02 - adduct much greater than for 47 (PEN) or 48 (POBN, by ca. 23-fold). Can be used to trap rascals in micelles.  

4-DOPPN 125 ph. 25 Can be used to trap radicals in micelles. Very poorly soluble in water and gives very broad EPR lines due to slow molecular motion.  

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